If he's only around 95%, it might make more sense for Spencer Carbery to play it safe, give him a few more days, and potentially bring him back for Game 6 if needed.
That said, it doesn't look like Carbery is thinking that way. According to sources, the Capitals series lead isn't factoring into the decision. Carbery made it clear that Protas will return when he's fully ready -- and by all accounts, that time is now.