The dragon has a Laser ability that shakes the church and some blocks near the towers. Phantoms don’t work at all with your custom towers. When the dragon uses its Triple Dive attack, it dives awkwardly under the church and then pops back up on top, which looks a bit silly—like it's rising from the ground like a zombie, and that’s not very impressive.

I assume you can’t fix these issues with this mod/datapack since it’s not based on JavaScript, and it seems that True Ending is likely the main issue. It would be great to add this mod to the incompatibilities list on your mod’s page.