Welcome to the forum its a great place to get your questions answered. I have replace and repaired domes however I have never use "marine adhesive". I would recommend removing the dome cleaning the area around it very good and replacing with good quality RV sealant and self leveling lap seal.
Jake my sidekick (yellow Lab) 10/04 - 05/20
2017 RAM 2500 CC 4X4 Cummins Diesel
2016 Flagstaff 26 FKWS
AF&AM & El Korah Shrine of Idaho