1) If you can make the payments, you have an obligation to pay it off. The condition of the unit has nothing to do with the responsibility that you agreed to take on.
2) Assuming the loan has the camper listed as collateral...yes, they can come take it.
3) If you make it difficult for them to get it, they can include the cost to do so when they total everything up.
4) You will still owe the $11k, any cost to repo it and probably some other fees and penalties.
5) Unless you are filing full bankruptcy, they can sue you for the difference and take other stuff from you.
I would guess you are in for $15-20k if you force them to repo it by the time all is done and said. Well worth the trouble to file against you to recover their losses, so unless you are otherwise without any assets probably not the best option.
Tammy & Mike
Ford F250 V10
2021 Gray Wolf
Gemini Catamaran 34'
Full Time spliting time between boat and RV