Dimension definition seemingly asking for a preset even though a list of biomes is present

To start, I'm just trying to update my datapack from an older version to version 1.21 (I think I was on version 1.18 originally, regardless, everything else isn't giving me any other errors) According to the wiki, when you're making a custom dimension and you're using the multi_noise biome source type, you can either fill in a preset or give your own list of custom biomes, the latter of which I have done. However, Minecraft is now giving an error that the preset key is missing in my file which seems redundant because I have a list of biomes. No key preset in MapLike[{"biomes":[{"biome": And from there it just starts listing my entire list of biomes with all their parameters. Regardless it seems to be completely missing the fact that I'm presenting it with a list of biomes so it doesn't need to ask for any preset. I've tried everything, comparing code from other datapacks, copy pasting code to see what makes the difference, using the preset instead of the list of biomes, using both the preset and the biomes (which doesn't work because those are mutually exclusive) but nothing seems to lift this error and I cannot figure out what the issue is. I have been using the Datapack Helper in VSC, and that doesn't give any errors, and I've been using Misodes's dimension generator (with the correct version selected) so in theory everything should work but it somehow doesn't and I've pretty much ran out of options, so now I'm asking here. That's the best explanation I can give, hopefully this is an easy fix because I'm losing my mind trying to find it.