but was simultaneously waiting for them to transfer him to a PRU, pending possible MD.
Soldiers are not 'transferred' to a PRU pending possible MD - they are assigned to a PRU, based primarily on clinical need, in order to recover. This may result in a medical discharge.
but the speed at which his MD came
...it would be normal to have 6 months service past confirmation of med discharge. I accept that this period passes extremely quickly, with housing and income stream the top pris, thereby pushing SC to the back of the list.