Cracking and peeling roof

Hi, I am sort of new here. We have a '97 Colman Santa Fe that has lived a full life! We just noticed that under where the awning connects there is part of the roof chipped away. Looks like water got into there maybe. We are planning on trying that flex seal (as seen on tv) to seal it up and maybe prevent more splitting. Has anyone tried this before? I have heard great things about what it can fix outside of trailers.

Also the rubber seal around the top is coming off. We have tried gorilla glue (I think it was) to get it back in place with no help. I plan on buying a hybrid before next summer so don't need to fix this stuff but would love to prevent more wearing or damage if it could be done easily.