I suppose there might be a way, but I don't know it. I feel like the vet might best be able to tell... If the frog isn't eating now something is wrong. It sounds like an impaction to me, I think you are right. Keep up the baths, and massage the lump very gently. Try the honey bath maybe. I misread earlier, and after reviewing your first post and not missing whole parts this time, it definitely sounds like impaction or some other digestive issue. If you can't get the toad to pass it , the vet will probably be the best option. When was the last time your toad poo'd?