I can't use custom aspects in triggers in 1.20.1 Fabric

I've recently started working on a mod to go with a modpack I made recently that will use me and my friends as inside jokes and our play styles, but I keep running into the issue where I can't use custom aspects (Mobs, Potion effects) in triggers, I tried making a block to summon a boss but it won't allow me to set the boss as a spawn it only lets me summon vanilla mobs and items, I tried setting a custom potion effect from an item but it doesn't work with the custom potion but it works with vanilla potions, just using the block coding but I'm not sure how to fix it or if there's a way to fix it with more in depth coding, I can add images if anyone has any ideas. Any help would be appreciated.