My solution for smells in the camper has always been simple.
Open all the windows, build a good smokey camp fire outside the camper down-wind. Let the smoke blow inside the camper. The smokier the better. Close up the camper a few hours. Then open all the windows and door and air it out.
It won't smell like mold any more, it won't have bad odors any more. But it will smell like camp fire smoke a while. That's a much better smell than some other uncomfortable odors. By the time the smoke smell FINALLY goes away, the original smell will be gone too.
I know this sounds a bit weird, I've posted several times and always get off-the-cuff responses (which is OK, I enjoy humor too, even if it's on me!). But, this does work. (Just be patient getting the smoke smell out of the camper. It can linger for quite a while!)