If the creditors come after your Father and they obtain a judgement against him they can try and collect on the judgement in various ways.  You are correct is assuming that one of the ways is to place a lien against real property.  What I am concerned about for you is that the creditors will try and set aside the transfer from you and you Dad t you alone as fraudulent.  In other words in an attempt to defraud creditors.  I think that you and your Father need to go and speak with someone to help sort out what is the best thing for you to do here with regard to his debts and your home.  You can not take him off the mortgage unless you refinance.  Seek help.  Good luck.