Am i a bad DM?
>running game for party with fey race character
>he has dreams of shadowfell monsters
>they eventually find onyx gem that creates huge aura manifesting many shadowfell portals in surrounding land
>whole adventure where they destroy it
>he starts having dremas of 3 shadar-kai
>suddenly meets 3 shadar-kai on the road
Session left off there
>planning to use the 3 shadar-kai from the Mordenkainens Tome of Foes, because i like the "group of 3 distinct baddies hunts the main characters" trope
>due to this fey characters unique link to shadowfell, they don't want to kill him
>just use him
>they're level 4 and the shadarkai are CR 7 9 and 11 so there's basically no way the PCs can win
>I wish the PCs had like a 25 percent chance to win, just to make it interesting
>if they lose the PCs are forced to drink a potion to curse them, but are spared
>the potion will compel them to do...something to assist the shadowfell invasion
>only issue is, one character already has a plot hook like that (he has a poison in him that's slowly killing him and he needs gold to buy the cure).
Am I a bad DM for doing this? The fight technically go either way but they'll almost definitely lose and be forced to go along with this. I want them to be able to level up and defeat these guys in a rematch later. Any ideas or advice?