Garry McGonigal wrote:
Once we protested and theys aw the red flag, they did their penalty
turns and were gone. We were still trying to get back to coruse and
up to speed and actually the offending boat gained substantial
course advantage through all of that.

Sounds like they were in violation of:

44.1 Taking a Penalty

A boat that may have broken a rule of Part 2 while racing may take a
penalty at the time of the incident. Her penalty shall be a 720 Turns
Penalty unless the sailing instructions specify the use of the Scoring
Penalty or some other penalty. However, if she caused serious damage
or gained a significant advantage in the race or series by her breach
she shall retire.

If the other boat gained "substantial course advantage", as you put
it, they should have retired. Doing a 720 is not enough.