If you look at the most severe PCS cases, two factors are usually involved - pharmaceutical drugs such as antidepressants, pain meds, or migraine cocktails, and multiple head hits.
I would advise against the migraine protocol because they usually involve those medications.
You mentioned - "It is important to note that the first literature review I cited states that prophylactic medication can only treat the headache itself and not the cognitive symptoms, so
it would seem wise to avoid head trauma to a reasonable extent."
A good way to avoid the minor head bumps is to wear a padded hat to protect the brain while it is recovering. The Ribcap is a good one:
Protective Special Needs Helmets for Adults & Children | Ribcap