
Quoting
flyingron
The problem is that in Wisconsin, it very much matters when things are recorded versus when they were signed. I'd hesitate to say that all you need to do is record a death certificate way after the fact. A title company can verify what the legal ownership is, at least to the point if you buy their insurance as to what they say, you'll be protected. However, if the fact that mom didn't make sure her interest received through survivorship was recorded properly, her quit claim to you may have only transferred her share. Deeds can't give up property interest you don't have.
In the worst case, you can bring a quiet title action to fix this (provided there's nobody else really wanting to contest this).