Hi, Desperate. Sorry but I don't have any really great ideas. Two things that you can try are an environmentally safe paint stripper like Citristrip and a heat gun. No guarantees with either. Try the heat gun first if you can find one to borrow or rent long enough to give it a good try. Then just a putty knife to scrape it off when and if it softens in the heat.
With the stripper, do a small test section and let it sit over night. Keep kids and pets away. Even though it is non-toxic, you can still get a chemical burn. Be sure to use eye protection and gloves when you are around it. If you put it on at night, and it's going to work, it should soften some by early in the morning.