Matches where a player loses more points than the won are kinda common, we see a few every week. Usually occurs when a player wins 2 close sets, often tiebreaks and gets blown out in the other set.
Rarely does said player have 3 or 4 such matches though. But they could have 2 where they lose more points and then 2 or 3 other close ones.
Say a player wins round 1 7-6 1-6 7-6 losing 7 more points
Wins round 2 7-5 7-6 winning 9 more points
Wins QF 2-6 7-5 7-6 losing 4 more points
Wins SF 7-6 7-6 winning 1 more point
Wins final 6-4 0-6 7-5 losing 3 more points
That player would have lost 4 more points throughout the tournament than he won. Has something like this happened?
As mentioned, seems like it would be very difficult to do unless there were a couple of 7-6, 1-6, 7-6 type scores with lopsided TBs to boot. Although such occurrences take place more times than one would think on tour, multiple occurrences involving the same player in the same tournament are rarer (either way -- losing more points and still winning or winning more points and still losing).
Slightly tangentially, if the ATP site's statistics are correct, one occurrence of a player winning a best of five match in straights sets while winning fewer points than his opponent is this one:
Agassi defeats Krajicek, Wimbledon 1993
7-5, 7-6(7), 7-6(8)
Total points won: