I'm glad you figured it out.
I can only imagine there can be issues if you try using both the mod loaders together(probably because they are loading the same stuff twice?)
But generally speaking if you are using Mattie's mod loader you shouldn't need my mod loader since it doesn't do anything fancy , at least for now.
And no need to feel embarrassed, i'm honestly impressed you manage to fix this on your even if it took you some time, because i'm not sure i would have thought of your solution, given that i don't test my mods with other mods(but if you ever face problems using my mods together with other mods let me know).