Great info! Still not clear why not 60 amps constant, but at least this time you did get constant amps as though the charger is a 53 amper. (Too bad no way to see if that is indeed a 55 amper)
Good thing you noted the rising temp too because: Your charger put out 123.6 AH from 1 till 3:20 and about 10 more to the end.
Total approx AH 133.6 AH into a 100AH battery. So where did the extra 33.6 AH go? Usually that would be to heat. Your temps rose by 10 degrees F during the recharge. Some heat was noted going to wiring /connections.