lump on foot

Our girl guinea Messi has a large lump with white dots on her foot. We have seen two vets multiple times to no result of what it is. We have had an xray in her foot which showed some deterioration on her toe the lump is joined to. They both suspect it is not bumblefoot and have had her on 2...

I'm extremely worried about my piggie Optimus as I gave him and his brother some veg and noticed he seemed to be numb in his back leg and on top of his foot there was a big lump with dry black stuff around his nails. It's not Bumble foot as it's on the top of his foot and I can't find anything on...