So i'm also of the opinion that heels should be cheating more to win matches but obviously it shouldn't be every heel and every match.
I get they're seemingly building Liv (hopefully) and want to some what protect her, garner sympathy for her and generate heat for Bex by cheating but I think they should gone another route with it. Given how they were playing up her nerves and it being her first big shot etc, I think they should have done it where she makes a mistake and Bex capitalises and hits her finish for the fall.
I'm not mad at what went down though, i'm fine (for the most part) with fucky finishes so long as it drives the story. For me, I don't need definitive finishes in every match like its MMA or Boxing or something.