Not completely sure I understand lucky's explanation of the paytable "decreasing" when you hit.
Can you be more clear regarding what you mean?
As it appears the "base" bet here is 50, the paytable seems to be:
Jacks/Better 1
2-pair 2
Trips 3
Straight 5
Flush 7
Full House 10
Quads 22.9 (??)
Straight Flush 120
Royal 500
As posted, the return is about 102.9%, which is still excellent.
But please explain what the "standard" pay table is for this game, and how/when that changes.
BTW, here is an odds calculator you can use:
https://wizardofodds.com/games/video-poker/analyzer/