I imagine this is some combination of having both Four Fingers and Shortcut, plus the Psychic boss blind.
I played five cards, four of which were suited and one of which was not. The Unsuited card was in the middle of the straight run, e.g.
2 of Clubs
4 of Hearts
5 of Clubs
6 of Clubs
8 of Clubs
When selecting just the 4 clubs, it showed it would score a Flush as expected, but said the hand would not score (5 cards required for Psychic). When selecting 2-4-6-7 it showed it would be a Straight as expected - again, the hand would not score. However, when selecting all 5 cards, it showed as a scoring Straight Flush. Upon playing, it scored as such.
A wild card was not involved, and I do not have any other jokers like Smeared Joker which would change suits (and in any case, the offsuit was a different color).
Very bizarre!
Attached are photos of my current game and deck - apologies I did not get a screenshot of it showing the selection/scoring.