"There was one particular object or organism that had tentacles coming from it...
... and it was able to lift itself up off the glass slide...
It appeared to be self-aware or able to grow or move in space.
https://mobile.twitter.com/jcho710/status/1443646378840756224
I read the article, it really is describing the relationship to bacteria colonizing the hydra. Not about hydra colonizing a more complex life form.
Was there anything that could show hydra being used as a transport vessel to get something into humans? They may not need to colonize but rather keep something safe for population.
I didn’t see anything like that in this article, not to say it would be impossible.