Because Wisconsin is a community property state, your problem is that the borrowing husband may only have a 50% interest in the RV unless the spouse agrees with the security interest. She does not need to be obligated on the note but must be willing to allow the security interest to attach. This could be solved by having the spouse sign the security agreement (not the note) and this would solve two problems:
- It will authorize any filing needed on the spouse (which may be wise), and
- It would give you a security interest in the spouse's portion of the RV, the other 50% interest.
If this is what a spousal consent does, then OK. Or if the spousal consent conveys to the husband the wife's rights in the RV, then, also OK.
Remember, it is the security agreement that give the security party right in the collateral and not the filing of a UCC or listing the lender's name on the title, as a lienholder. A UCC financing statement or a title protects the security interest from other creditors, but only if you have a security interest to protect. It doesn't give you a security interest. That is what the security agreement does.
Having the spouse sign the security agreement is the easiest approach to solve your problem, and I like easy.