Obviously there are a lot of possibilities. But old Quran manuscripts are quite many And there are only minor variations between them. And these variations are not like normal variations. Beside mistakes they can be classified as alternative or maybe equivalents.
Anyway I don't think the text is understood correctly nor the current understanding is even improvable. Because of the ambiguities it is really hard to motivated to put effort. There are quite a lot of possibilities. If it was changed and various actors hiding potential originals. How can we know. We depend on the available manuscripts. In case of aliens there are crazy possibilities. It is possible it was intentionally made hard to understand. It is even possible that it may intentionally orhestrated to look like changed version of an original book. Because the original have straightforward language under normal conditions it may make it look like widespread versions were changed. However obviously this would be a plot by aliens. And likely current widespread versions may be involving pretty crazy things. But in that case it is probably only up to aliens to reveal it. It seems like this possibility is really strong but still Quran may be pretty straightforward book and only reason may be unconventional alphabet behind problems with understanding.
Not that I claim Quran itself is not original or there is even a claim of a other original but obviously there are lots of suspicious things are going on and aliens will exploit any opportunity to maximize convict people based on intent even where there are no actual consequences they may make it seem like there are consequences so it is real conviction.