I wouldn't say that it's unbelievable that Darby can beat Cage.
It's more so that you make Cage and Taz less believable in the aggressive shyt-talking department. You call Moxley p*ssy for weeks and then throw in the towel sympathetically.
At WORST, you have Taz pull the ref out for a DQ or stomp Mox before Darby saves... That's wrestling 101..
...and that's if if you'd rather not finish it with Darby interference for a DQ to continue his heat with Cage and hint at future smoke with Mox down the line.
Having Taz throw in the damn towel tells us, "Mox was killing the heel monster "fukk The World" CHAMPION so badly that even Taz couldn't bear to watch him suffer.
Then having Cage not sell it like death to legitimize it....
...then having him heelishly get over on Mox afterward and Mox no-sells THAT says, "In case you weren't certain, he IS indeed all talk and a threat to no one."