Some people are different. If I feel that someone has insulted my wife, I'm going to take as much time as it takes to make sure they understand where the line is. Saying "I'm sorry. I meant nothing by that and I sincerely apologize. I meant no disrespect to you or your wife" doesn't take 2 minutes to say. If I had to guess, I'd say that Watson told him how he crossed the line and there was some push back rather than an immediate apology. That pushback required further "encouragement" towards the appropriate response.
If someone tells you they are offended by what you did or said, the first response should be an apology. It might get left at that or it might get explained so that it doesn't happen again. Watson doesn't strike me as the type of guy who wouldn't accept a sincere apology. They are both professionals. I just wonder why it took so long for the other guy to come back.