The call sign "Lifeguard" is only reserved for aircraft who are actually transporting an injured person (or on their way to pick up one). The aircraft type does not matter, and use of the word "Lifeguard" implies that a controller will provide priority service to that aircraft. It's a civil aviation term; if a military aircraft wants to use the term "Lifeguard," they must request permission. And saying "Air Evac" doesn't usually cut it.
So yes, it sounds like both aircraft were air ambulances.