A moisture meter is a very useful tool to have when you own a camper, but since you have already pulled up the floor covering, you could use a small hole saw to remove a plug of wood flooring. That will tell you tell you the condition of the wood below and you'll know if any mold is present by what you see and what you can smell.
If it's become damp you'll have to first find the source of the water intrusion and fix it, then cut out the affected area and replace that along with any insulation below it.
1992 T-2470 (now residing in South Carolina)
Current Sunline-2007 Solaris 2499
2018 Silverado 1500 w/Max Trailering pkg.