The photo is helpful but lacks some detail and perspective. I tried to enlarge it but it "pixelated out." If you could obtain at least one "full Kevin" view with the wound site included so it can be seen where specifically the wounds are located and several more close ups from different angles and perspectives it may be more helpful. Do the wounds appear to be lacerations or healing lacerations, abrasions or even burns? Is it possible that Kevin was attacked by another animal such as a cat? IF so and by a cat; there is a particular bacterium present in cat's mouths called Pasteurella that commonly causes infection in bitten animals and humans. Fortunately, the Augmentin your are administering to Kevin will cover Pateurella and many other bacteria as well. The unsteadiness you mentioned may actually be related to an injury and if this scenario is accurate, a fracture is also a possibility. Unfortunately, this would likely need to be diagnosed by an x-ray study which may prove difficult to obtain in a State where captive wildlife is illegal. I doubt that Kevin has become "acutely" malnourished and even if she was malnourished, you are now supplementing her intake with Squirrel Block "gruel" compliments of CritterMom! Unsteadiness may also be associated with infection which I still suspect is a factor with Kevin but unsteadiness can be associated with many other conditions including direct trauma, neurologic injury (head or nerve injury), poisoning, and many others. Overall, it seems that Kevin is slowly improving and obviously that is very good news! Please keep on with the antibiotics and fluids. It's definitely good strategy to keep the "gruel" going as not only is Kevin getting nutritional support with this, she is also getting supplemental fluids; but please continue directly supplementing fluids with readily available water and the formula.
Best regards,
SamtheSquirrel