Ice cream technique - what should I mix into what?
I usually beat two whole eggs with an electric mixer and then slowly mix the sugar into the eggs before adding the cream, milk, and flavoring. I've never had a problem with the egg whites that way. In your case I'd do the same but treat the beaten egg whites and Rich Whip as the "additional dairy" to be added after the egg yolks and sugar are slowly mixed together.

I've never actually tried whipping egg whites for an ice cream recipe -- my guess is that any air it contributed would be immediately removed once the ice cream machine started turning. It's the ice cream machine's job to incorporate air into the mix anyway. But it might be worth a try.