Mahut has won both their previous meetings. Their last match was earlier this month on grass. He won in 3 sets after Querrey took set 1 in a tie break.
I feel Querrey will have been affected by his win over Djokovic. He normally doesn’t get a lot of media attention. He is a bit goofy and more than a little dull so the attention he will have had since Saturday will have been out of the ordinary for him. He did extremely well to hang on for the win even though Djokovic clearly was not near his best. Many players would have crumbled just because of who they were playing.
Mahut has been playing well on grass. He beat Ferrer in the second round in straight sets. He dropped a set in the last round to Herbert but losing set 3 when you are 2-0 up isn’t a massive issue in slams.
I think they are close enough on this surface to say value is on Querrey but not many people beat Djokovic and it almost always affects them for a few weeks afterwards.
If you can get on Mahut above 2.10 take it.