It still comes down to this: you can't permit a situation competitively in which whether a player knew he was on two has to be interpreted.
It is quite possible that a Souquet or a Robles would handle the situation differently, but it would still be inappropriate to call a fifteen point penalty on oneself after the third foul. The moral "high-ground' would be to announce to opponent that "I am on two fouls" prior to shooting, thereby establishing the needed recognition situationally. Then, if one fouls, the penalty would qualify under the rules. If my opponent told me of a third consecutive foul after the fact and I had not warned them, I would say "the penalty is just one point, for you were not officially warned." That's also the moral high-ground. In the situation reported in the Hopkins match, if both players took the moral high-ground, the penalty would have been just one point, as Allen's offer to take the penalty would have been declined.
Just one man's opinion, and I'm a sportsmanship fanatic.