You got that right. The concept of resurrection is quite confused in Judiaism: As you say:
"In Ecclesiastes, the scripture indicates that you do not know your appointed time of death(9:12) and your body is going to the grave(9:10) or its long home(12:5) awaiting the resurrection and your spirit returns to God(12:7)."
What do you care more about, your body or your spirit? The jewish concept of ressurection is inconsistent with all other religions. Even Christianity. If your soul is already in heaven, what do you care what happens to your body. Let it rot. Let them all rot.
But your impression of the concept of transmigration based on that link is not quite accurate.
Where to start. One place is that the words of Moses, and indeed Abraham were entirely oral, and passed from generation to generation orally for hundreds of years. Then at the Babylonian exile, the priests decided that the laws and history at least should be written down and the Torah was written by them. But they did not write down the entire oral tadition, at least that is what jewish scholars say.
Some of what is called the secret tradition got written down in the Talmud as commentary on the Torah. Other parts got written down in the group of books called collectively the Kabala, which includes the Zohar.
The earliest roots of Kabbala are traced to Merkava mysticism. It began to flourish in Palestine in the 1st century AD and had as its main concern ecstatic and mystical contemplation of the divine throne, or "chariot" (merkava), seen in a vision by Ezekiel, the prophet (Ezekiel 1).
The earliest known Jewish text on magic and cosmology, Sefer Yetzira ("Book of Creation"), appeared sometime between the 3rd and the 6th century.
The author of this book is Abraham. It had been passed down in secret for centuries.
It explained creation as a process involving the 10 divine numbers (sefirot; see sefira) of God the Creator and the 22 letters of the Hebrew alphabet.
Taken together, they were said to constitute the "32 paths of secret wisdom."
The creation process in this book is amazingly close to superstring theory which requires 10 dimensions. Abraham even specified how 6 of the ten dimensions compactifies or rolls up leaving just our 4-d world in creation. The 22 letters are qualities that come from compactification of 22 of the 26 dimensions of simple string theory which is the unified field. This is proof that god created physics and used it to create the world. Jesus knew all this but the Jews were not ready to hear it.
String theory is based on a 32 fold symmetry, also specified by Abraham. The Book of Creation was the first of the secret tradition to be written. We had to wait centuries for the next installment.
A major text of early Kabbala was the 12th-century Sefer ha-bahir ("Book of Brightness"), whose influence on the development of Jewish esoteric mysticism and on Judaism in general was profound and lasting.
The Bahir not only interpreted the sefirot as instrumental in creating and sustaining the universe but also introduced into Judaism such notions as the transmigration of souls and strengthened the foundations of Kabbala by providing it with an extensive mystical symbolism similar to Hinduism and Buddhism.
So although your link suggests that transmigration was a recent concept of Judiaism, it was there from the beginning, just as the creation process was. It just was not yet written down.
Now god of course knows whether string theory or reincarnation is correct. If they were not correct, why would he specify its physics so exactly and tell Abraham. The same goes for Transmigration.
"The spirit returns to god." In another old testament scripture, it returns again and again according to jewish interpretation.
The jews did not have it all right from the beginning. For example the concept of the soul came from and was originated by the Greek philosophers. The concept of reincarnation was invented by Gautama, the Buddha. He interestingly also is credited with originating Indian logic. Funny but gautama rejected the concept of the soul. God would not give everything to him.
In pre-christian Judiaism, the soul was not destined for heaven or hell. People just died and took refuge that there bodies might some day come to life. There was no concept of the soul going to heaven. Soul meant something closer to self than the Greek meaning.
Jesus introduced the idea that the soul could go to heaven. But the Jews were not ready for another 1000 years to accept that teaching. They finally did with the Kabala, but that still remains a controversial part of Jewish thinking, which sadly has become rather atheistic I must admit.
So god did not give everthing to anyone right away. He waited until each was ready. But he knew everything, as did Jesus , all along. And the Book of Creation proves it. He knew all along what we are just learning today in physics.
By the way, the Hindus knew about quarks almost two thousand years ago. They knew that you needed three quarks to make a proton or neutron that could be observed whereas quarks could not be observed. They also knew about the creation of multiple universes. Something we are just learning about today in cosmology.
But the jews knew about evolution. They knew the order in which life appeared on the earth, except they got the sun being created after vegestation was created. Only one day off. Their characterization of the big bang generating light from the void is pretty accurate as well.
So the point is that almost everything we know today in science can be found in various ancient religions. To me that proves the existence of a god- at least one that is a product of a prior intelligent civilization on a different planet, and possibly one that was around for the creation of this universe. It does not prove he created our universe. But scripture in all religions make this claim, and other religions than judiaism and christianity have much more detailed accounts of the whole creation process.
So bottomline, there is one god for all religions and god did not give everything to any one religion. So to get the most accurate picture of god and his creation, you must study every religion. That is what I have done. And that is where all my concepts like transmigration come from that you find different, to put it mildly.