I set up a mob spawner in a Void Dimension from Just Another Void Dimension. Waited about 10 minutes and nothing has spawned yet. I put some modifications on it like redstone control, but it still hasn't spawned anything yet.

I'm on TNP Limitless 5.

Is it spinning? Redstone control requires a signal be applied to the block or it will not tick (indicated by spinning or not). I'm not sure if that lever is on/off or if a signal from that spot will even be applied to the spawner

Is it spinning? Redstone control requires a signal be applied to the block or it will not tick (indicated by spinning or not). I'm not sure if that lever is on/off or if a signal from that spot will even be applied to the spawner

It is spinning, yes. The redstone signal is on.

Try throwing ignore conditions on it and see if that works. I think wither skeletons either have a requirement of spawning in a nether biome or on nether brick blocks.

Try throwing ignore conditions on it and see if that works. I think wither skeletons either have a requirement of spawning in a nether biome or on nether brick blocks.

I don't have a dragon egg yet, and I'm worried about using up the dragon egg. Not sure how to get more yet besides the dragon.

I feel like i had the same issue with 1.18.1 + 2. Try placing the spawner in the air and see if that helps. That fixed it for me.