Leak in Coroplast Near Pull Handle

[Lhinkle114]

I need the advise of all the intelligent Montana owners. I have a 2019 3791RD that has a minor leak coming from the hole in the Coroplast where the kitchen grey what pull handle comes out. Funny thing the leak stops when I close the grey tank. It could be grey but does not have any smell in the very small pool on the concrete. Before I drop the bottom any idea what I might need to get to fix before I start.

Thanks for all the help

Larry