That is probably more tricky then! I have 2 boars that used to live together and fell out and I had tried 3 times since then to bond them, but no joy. As a last resort, you could try bathing them together using Gorgeous guineas shampoo. This will make them comfort eachother as most guineas dont really like a bath and they will smell the same. Then put them together in a neutral area with new toys/tubes etc that bears none of their scent and see what happens. Be patient though, it can take hours or even days. Dont be alarmed at rumbling, bum wiggling, mounting etc, this is all normal. It is only if they actually lunge at each other that you should call it a day. You need to be around whlst they are together to make sure all is ok.
If this goes well, make sure their hutch or cage is completely disinfected with a safe small animal disinfectant, new bedding and toys and rearranged etc before putting them in there together.
