ya. even at 80% 5rm it's tough. i've gotta talk with them and come up with a plan. i train to surf and want to surf more than anything.
There's a training stimulus curve/intensity and I'm guessing the last two or so reps on sets 3 through 5 are giving you very little physically and depending on how you feel about the value of grinding out sets very little to a lot mentally.....and this is supposed to be your best stimulus day.
I would try a few things.
Continue program but reduce intensity. First, there's no reason to do 5x5 just because the program says so. I would always every time start out at 3x5 and see if that's enough. If it's not providing enough stimulus for strength gains I would then add a set and see if that drives a change. If that doesn't drive adaptation over a 2-4 weeks it's time for a program change. 5x5 at a static weight is less effective than a top set followed by back off sets at reduced intensity. The top set gives you the mental and physical training you need to stay acclimated to pushing or pulling hard and the back off sets give you the training stimulus you need to get stronger.
Bridge 3.0 .....and if fatigue is still a factor reduce RPE by one and continue the program. It's the best intermediate starting point program I've used and simple modifications for specific trainees continue to work.