You're quite correct in that the article shows that RNA from the virus (and other viruses) can alter the DNA by a reverse transcription mechanism. It's true it didn't look at the vaccine. However,
reverse transcription mechanisms occur in our own cells, so once the vaccine releases RNA into the cell, can we be certain the body won't see it the same as RNA from the virus, and therefore incorporate it in the same way by the same mechanism? No, we cannot be certain at all.
This is actually really new research because it has long been thought that DNA to RNA transcription was a one-way process, but we're now learning different. Reverse transcription is now believed to be used in our cells for processes such as DNA repair, for example. Here's a quote from research published in June this year looking at the human enzyme polymerase theta, which they found can act as a reverse transcriptase in relation to HIV:
"
In a series of elegant experiments, the researchers tested polymerase theta against the reverse transcriptase from HIV, which is one of the best studied of its kind. They showed that polymerase theta was capable of converting RNA messages into DNA, which it did as well as HIV reverse transcriptase" (
Discovery Identifies a Highly Efficient Human Reverse Transcriptase that can Write RNA Sequences into DNA)
Could this happen with covid? We don't know. We're playing with fire and have no idea what kind of fire we're playing with.
ADE is a long-term effect and so we wouldn't necessarily expect to have seen anything yet. ADE may not be seen for a couple of years or even 5-10 years. If it occurs it can be deadly because the antibodies created in response to the vaccine actually enhance the virus's effect and make the disease far worse for the vaccinated than if they'd never been vaccinated at all.
It's good that they're monitoring it, and as I said the papers I've seen all say the same thing -- it has not been seen yet. In other words, so far so good, let's all hope for the best. But you cannot get 'de-vaccinated' can you?