Sorry if this question has been covered before:
Yesterday my playing partner was having a good game, then he hit a ball into the scrub,
I was on the opposite side of the fairway and played my ball before walking across to help look for his ball. Buy the time I had got to his ball the 3 minutes was just about finished.
The 3 minutes to look for a ball starts when the player starts looking, so to be competitive can the player wait on the edge of the fairway until all 4 in his group have arrived to start looking at the same time.
Making the 3 minutes more affective
The three minutes starts from "when the search begins", not necessarily from when the player whose ball you're looking for starts searching.
In answer to your question, yes you could wait until all are present, but that's hardly the 'right' thing to do. The change was instigated to minimise delays, not add extra delays because someone has a stopwatch.