Thanks for this fic
Like Eliza Bennett, I'm reluctant to comment where I don't think my comments will go doen in (local) history with the eclat of instant proverbs.
Not that I can meet that standard here, but I don't think anyone else has commented on the fact that you make it that attending to their former (grossly misjudged and belatedly grieved) colleague's corpse that determines Pomona to let herself finally be healed. To the extent that that is possible.
In a fiction filled with verbal and emotional felicities, that's one more worth specific mention.
I think Snape would have liked that repercussion of his demise. A part of him always stood for healing.