>>32786350No.
The Rock-part of their "original form" is the reason some bodypart of them was well preserved enough for them to be able to be revived in the first place...
Suggesting that there was a different "original" version in the first place means that you either think they were literally the same in every way (no design change either) except the lack of the Rock-type (which is bullshit, because the Rock type is inherent to them in other ways, like their moveset, the fossil-item usually being a "rockier" bodypart like shells, or directly implied in their design), or you think they looked different, had different movesets and everything, which would basically make it a different Pokemon, ultimately contradicting the whole idea of "bringing back THAT pokemon that became extinct"..
The other thing is.. this idea of brining back to life extinct creatures is basically as simple as this:
-obtain well enough preserved sample
-extract the complete DNA
-create a clone
which strongly implies the "fosill pokemon" we know are the same species that went extinct.
Whereas the "maybe they weren't Rock originally"-side would imply the "+Rock" version is exclusively the result of reviving a fossil (still dont see how u get around the cloning issue since it's not like the whole body was preserved and they're given an electric shock to wake back up or whatever..), in which case we would probably see evidence in the offspring (since it doesn't undergo that fossilisation+revival process).