Modded Bosses Not Spawning On Server

As the title says modded bosses from the thorium, spirit, tremor, etc are not spawning when I use the item in multiplayer, however they do spawn in singleplayer. It makes the noise then nothing happens. I do not know if this is a server sync bug or something, but if anyone knows a fix that would be great.

Mod List:
"ItemChecklist",
"HelpfulHotkeys",
"AutoTrash",
"LootBags",
"MoreAccessories",
"WMITF",
"WingSlot",
"imkSushisMod",
"HEROsMod",
"MagicStorage",...

Modded Bosses Not Spawning On Server