So sad to hear about that. I know about MRSA, but a quick internet search and I learned more. The dog version is "While MRSA is a major issue in human health, dogs are more likely to be affected by a different bacterial strain called methicillin-resistant staphylococcus pseudointermedius or MRSP."
It does need careful attention and can be effectively managed and possibly controlled. A second opinion is a MUST. Lab testing for EXACTLY what is needed.
Keep us posted,