Barney, I am looking at those type products, but the area of the wood is soaking wet, and has swelled up a good 1/4" so the floor is not flat in those corners. I'm not sure I could dry it out enough for those products to be effective and get a floor flat enough to put vinyl flooring on.
The root cause of the water intrusion seems to be the sealant the factory used on the bottom and sides of the OSB. Bottom was fine, but the sealant is cracking on the edges allowing water to wick in the ends. Fixing this corner is only delaying the issue until the water comes in through another crack.
Ideally I'd like a plywood floor because it's stronger and won't flex as much and also is sealed better. What I may do is use the Git Rot or similar on the edges of the NEW floor to completely lock out any water.