Thank you for this interesting case, Majda!

Regarding the UDIN and the primary reaction of "pigment plus", I am thinking of a defilement conflict of his face (and later hands) because of the accusation. Even when the pigment layer belongs to the ((Integumentary - Skin - Epidermis|epidermis)), it often reacts to give more ((Integumentary - Skin - Dermis (Leather Skin)|protection)). If this is the case, the following loss of pigment might be a symptom of repair, or a result of the ointment. I assume that both contact (new brain) and protection (old brain) themes are involved here. 
The development shows that he couldn't yet fully heal the conflict, but that it sensitized him for possible attacks. His tendency to avoid confrontation and to have a negative self-image seems to confirm that. Weight gain can have to do with this, there are several mechanisms that could be at play here.

His integrity seems to be a big value, perhaps prohibiting him to "make friends" and feel safe in the sun, or with others?
I like your META-meaning!