jd,
"if" you can get that problem area edge loose,,,,
what works excellent for me is binder clamps (see pic) from a office supply store
stretch out the vinyl and the wrinkle, a couple of inches at a time, and secure with the clamps every couple of inches....
they do grab and hold like a SOB(!!!!) while the glue cures!
if you re-do it all,,,do give them a try,,,
if you re-do it, stretch out and glue/clamp secure across the car and leave it over night,,,,do front to rear next day which is where the most stretching is normally needed...
I'm not a pro,,,but have been complemented on several I have done that way with the clips....
(almost makes it easy to do)