You used level 26 unboosted stats as the basis for your argument, so those stats are what I factored in for your 1v1 matchup. Procerathomimus does have evasive stance, like I said, but precise rampage hits through evasion, meaning Procerathomimus would take damage whether it used Evasive stance or not, as long as Erlikospyx made the logical choice of opening with MSS.
As for an uneven matchup, those are irrelevant when it comes to which dino is strongest in general, as opposed to one unfortunate matchup. The general ranking of a dinosaur based on strength does not depend on what level you have it at.
I say Erlikospyx is better not out of experience, but based on the fact that Metahub lists it as a Tyrant. As for it being underrated, if you mean people don’t use/talk about it as much it’s probably because they’ve already invested too many boosts and levels into other Tyrants to begin working on a new one, especially when its ingredients are relatively hard to get.
And yes, it is true that Erlikospyx can now be one-shot KO’d by a Procerathomimus with a Rampage ready, but that doesn’t necessarily make it the better dinosaur. I suppose we’ll have to wait for 1.8 to see which one prevails.