Crafted an Abyssal Chasm map which didn't feature an Abyssal Chasm, when I did locate biome once at the location the map told me to go, it said the closest one was 5000 blocks away from where the map had taken me.

In my play-though I have tried toxic and primordial maps, and these have worked. Not sure if this is specific the the chasm, but it seems likely.

You wouldn't happen to be running deeper oceans / tectonic / terralith would you?
I'm aware of at least the deeper oceans mod/datapack mucking with Chasm generation, and I suspect that other ocean worldgen modifiers might do a similar thing, which might be causing your issue

I am running none of these mods. The only terrain generation mods I'm running (barring Alex's Caves) are all the Yung Mods.