Your math is a little off - I get the following:
Distances (miles): 4.49, 8.24, 11.61, 5.49, 25.36
Times: 0:33:41, 0:58:58, 1:19:29, 0:45:41, 2:46:33
Total Distance: 55.19 miles
Total Time: 6:24:22
Average Pace: 6:58
Still pretty fast in context of the full journey.
If we take out the 5.49 miles @ 8:19 pace it becomes
49.7 miles
5:38:41
6:49 Avg pace
Again, fast given the context of the full journey, but broken up into runs across a day might be doable. 7:04 is WR pace for 100 consecutive road miles. 5:50 pace is the North American record pace for 50 consecutive miles (as best I can tell). So even if he had claimed to do this all in a single run it would still be a minute, or 17% over WR pace. Break it up into 4 legs throughout the day and it becomes a more believable feat.
Still though, it's tough to accept in the context of the super high-mileage journey, and really tough to accept given that his unsupported marathon PR pace is claimed to be 6:08. This collection includes a single run almost marathon distance at marathon PR pace + ~10%.