The Retch + Crown of the Pale King interaction

I'd like to know if you will heal from the reflected Retch damage with this item combination. It seems like you should but there's no good sources proving either way. Also, I'm not sure if you would heal based on your outgoing reflected damage or its value after the enemy's damage mitigations. Thank you for reading

The Retch doesn't reflect damage, it applies your life leech as damage to enemies.
To reflect damage, you first need to be hit, which is not necessary for The Retch. And since it's chaos damage, it couldn't be part of reflected damage anyway, even if it works instantly with Vaal Pact (not that that's going to be an issue for long anyway).

The Retch's damage counts as reflected damage, it's on the wiki and was stated by GGG.