I’m all for repairing carbon (yet you see a frame that I wouldn’t say was repairable) but rims with the concentrated loads they have are normally scrap – which is what I’d say yours is without a decent understanding of carbon repairs 😥
EDIT: Tried repairing a similar damage on an Enve for a mate, lasted ~2 weeks before spoken went loose. In the end we ended up dremeling the whole area away and rebuilding it back up, looks ugly and was lots of work but think it’s still going tubed as a winter wheel
EDIT2: just seen it’s in the rim bed not the section taking the load from the spoke, is that also damaged? If not, I’d do as you suggested – runny epoxy to bond whats left togther