I think Elidibus is the Aulus Mal Asina, the figure we see in Garlemald, and Aulus, both fit Elidibus' build, not to mention, Varis would be taken aback that the scientist that Varis valued is actually an Ascian.
I think it is more likely that Elidibus will have stolen Varis' body and used the Empire's Allagan tech to rebuild him, possibly hypertuned. If Zenos is to come back, he will have to pay a price for his 'death', bringing him back hale and healthy wouldn't feel as good narratively. Elidibus infiltrating the Empire would actually be a decent twist, and would explain the creepy turn that the Magitek has started to take since the Empire lost Nero.

Aulus, Elidibus and the figure all share the same type of clothes too.