I have read the previous thread (#4073) which reported coke ovens not working on multiplayers servers, and it was said it has since been fixed. However I am now having the exact same problem where the Coke Oven does work in my singleplayer world, but not in a multiplayer server.
I can build the oven using 27 coke bricks, then i use my engineering hammer on it which creates the oven and I can open it, put a bucket in it and some coal, but whenever I exit the oven it just drops my items, neither does the little flame turn orange.
I am using the 'all the mods 6' modpack, but I have seen that the updated version of ImmersiveEngineering that they use is: 'ImmersiveEngineering-1.16.5-4.2.4-134' so this is not an outdated version and the fix should've been applied.
Is it possible that this bug has occurred again?

Yeah it's ATM's fault. They know about it, they will fix it.

Not an IE issue.