Sentinels -- Hippocratic Oath + Nemesis Bonus

So a discussion about OblivAeon pointed out that, because the Sentinels all have the same Nemesis icon, they should do Nemesis damage to one another.

So, given the wording on Hippocratic Oath, if you chose Dr. Medico to do damage to Mainstay, would the Nemesis bonus be included in the amount that he heals? Or does the healing preempt the damage calculation?

Related question: Do damage buffs like Inspiring Presence or Obsidian Field affect how much Dr. Medico heals someone with Hippocratic Oath?

If Dr Medico is hitting another member of the Sentinels then yes the healing would increase by one.   Any other damage buffs would also increase what he is healing when Dr Medico would deal damage.  

Yes, you work out how much damage would be dealt, but when you get to the point where you would remove hp from the target, you add them instead. It's the same with, say, Ab'Zero when he deals himself cold damage when both the Focused Apertures and NPCU are out :).

The target of the damage does not need to be the target of the healing. So even if Medico wants to heal another hero (like Scholar) he could select one of the Sentinels for the damage (excluding himself) and still get the boosted healing.