Yeah, using a virus is a common method in microbiology research as a vector to transform a cell with genetic material from an external source.
A lot of produce in American marketplaces have been transformed with genes from fish that mimic antifreeze properties so they stay fresh in your fridge.
Source: I'm a microbiologist.
Anywho, the quantum biology thing is interesting. Kala uses the virus to inject the HNA for stability, but it is interesting that it looks to be only initiating the stability, not maintaining it. Otherwise, a dead Monster would essentially melt if it needed a consciousness to maintain the HNA structure.
I stand by the inclination that the Monsters existed in Cherenkov space and we started traveling through it, attracting their attention. It seems that the Monsters need an anchor to our dimension and the eggs do such.
I could see the Bohrium playing into the metabolic process of the Monsters, but I don't understand why the Monsters destroy our Patterson devices if that is the case.
I feel like their intent is to keep us out of their dimension by any means possible more than necessarily for sustenance, but I could be wrong. It just doesn't make sense. In game, the Monsters can eat just random creatures to fuel their growth and development, plus there doesn't seem to be much indication of what they do after a world is destroyed. Do they just die? Do they travel back? Once the Bohrium source is exhausted, what then?
If a conscious creature needs to maintain some sort of focus for interdimensional travel, I'm not sure how that would tie to Kala's ability, which would make sense if only she could teleport, but would not explain anyone else, unless she merely acts as a key.
On a biological scale, if HNA evolved for the monsters naturally, it would imply that there is an entire ecosystem in Chereknov space where such creatures evolved. Which might literally be like digging straight through a universe just by diving into C-space.