I'm not too sure there is any adhesive (glue) involved......you have likely snapped some of the inner clips off but the body shop will see that when they remove it.
As far as corrosion.....the cover you are referring to is RS specific.....that means non RS cars have the rocker exposed.
RS or not, the rocker is fully primed and painted.....your covers were painted prior to installation, so......yes, they will corrode but not because of the covers being pulled back.
From time to time, you should pop the jack access covers off the panels and thoroughly rinse the insides front to rear.
This is because mud and debris (including salt buildup) gets caught between the covers (plastic) and the real steel rocker panels.
Hopefully, when removed, the covers inner clips snapped and can be replaced so they fully seat again.
Rob