Well 1st know that their infection doesn’t just draw out. It’s more like a cottage cheese consistency. If you make a small cut, you would have to more then likely squeeze it like a pimple, which will be extremely painful for them. If you do draw out fluid, like clear fluid, it would probably be joint fluid. Once you cut and remove some of the infection please know that she will bleed a lot. Pack it good with neosporine and wrap it good. You are going to want to make the bleeding stop so wrap it tight but not too tight that it cuts off circulation to the area and let it be for a good 24 hours. Following that you are going to want to soak it every day for weeks to come. Wrapping it after each soak.
I am not trying to scare you I just want you to know what can happen. Just make sure you have everything laid out and ready to use. You will need vet wrap and good premium cotton balls.