We have the same dang problemA mouse got in the house. I have tomcat bait out. The dang mouse ate all my tomatoes and herbs I started! I am so angry.![]()
have you tried steel wool,find entry point pull apart place in entry point, fill with filler done, bait is also good.
rotten good for nothing/ attack 
I don't think I have ever heard of mice actually eating through the floor!!! Sounds like a bunch of poison under the house is needed. Or a couple of cats down there.