[Nevadaref]

While the failure to award the merited free-throws to B1 is a correctable error according to 2-10-1a, the time frame allowing for correction has passed in your senario. I know this because you stated, "Play continues for several minutes with points being scored by both teams." Since the ball becomes dead after a goal is scored, you have had at least two dead balls (after a basket by each team) after the clock properly started following the error. You must catch the error by the first dead ball after the clock starts following the error in order to correct it.

Look at 2.10.1 sit B, it details this exact error as no longer correctable for this specific reason quite clearly.