>>55128568It's a safe bet to assume Heath's own dreamlike experience was him meeting an alternate version of himself that was outright unrecognizable, and much like what we do with the professor, they ended up comparing notes, which is how he ended up with picrel.
But that's the best I have on "what the fuck happened to him" with our current evidence, the rest hinges on if Horizons will tell us more about Terapagos in more fluent detail or not somewhere down the line so we can better understand how its abilities played a role in SV's story.