so in the config i have this large list of custom names im using, but ive seen that it doesnt go through anywhere close to the whole list before using the default names again

Closing since 1.12 is no longer supported and this is caused by names being generated on generation, not on discovery.

Are you placing them by hand or exploring with world gen enabled?

Names get chosen once they're generated, not when they're found. So the others probably generated, you just didn't run into them.

all world gen, and usually ive only found 5-6 out of like 60 before it going back to default