Hey, recently one of my buddies created a PaperMC server for us to play on, and while the world was initially created in 1.15, it was quickly updated to 1.15.1 as we were experiencing assumably client side lag issues (before the Wither Skeleton Skull grind began). On this server I killed a total of 102 Wither Skeletons according to Statistics, but never received a Skull; even with Looting III, I was apparently supposed to get at least 5 or 6 on average. I assumed I was getting unlucky and we decided to put the project of a Nether Grinder back for a bit later.

Lag was built up and we decided to purchase a realm to play on, so the world file was transferred to myself to upload to Realms. We've now built the Nether Grinder to kill countless more Wither Skeletons with absolutely no skulls whatsoever. I've read a few of the other posts like this that show some sort of third party datapack that when updated (from 1.14.2 to 1.14.3 in their case, different for ours) caused some of the issues - we didn't have any of these, only a Bukkit datapack that when deleted and reuploaded didn't change anything.

Any help on this matter would be appreciated; while we've been cheating a little the whole time I think giving ourselves Wither Skulls is a bit too much. Thanks!

World is located here: https://drive.google.com/file/d/12ZcTF4y8k2nVAL0XR2F9YYmJGZ9tvc2S/view?usp=sharing