Tyrannosaur lips? Probably not...

Interesting. I mean this is only for Daspletosaurus, other tyrannosaurs and predatory dinosaurs, or just dinosaurs in general could still have had lips. This does raise the question whether or not these modern day ideas like a feathered and lipped rex are legit or not.

Yes, the only definitive answer is that D. horneri did not have lips.  HOWEVER, using phylogenetic bracketing, it is a good bet that other tyrannosaurs had the same trait, just like it was used to hypothesize that all tyrannosaurs in North America also had feathers.