In General Washington’s time, the military needed every available warm body.
Not quite so. Even Washington was reluctant to use irregulars like the militias.
In any case, an MD like Lakn is worth his weight in gold. Most of those in service are weighed in silver, maybe a silver-copper alloy, a billon. It takes many years to train an MD, and only a select few make it through training. To have one with experience at a war zone? Even more.
The penalty applied to Lakin is IDIOTIC in that regard. Shoot your own leg off idiotic. Doctor Lakin BEGGED to return to service.