Antistasi version:
Antistasi Ultimate

Faction setting:
MEI rebel, EF MJTF occupant, IDF invader, Aegis ION rival.

Problem:
IDF infantry don't spawn when IDF is set as invader. Garrisons doesn't spawn in outposts [1] except for empty vehicles. QRF works but vehicles are empty, except for crewmen. I cannot see anything wrong with military bases. Roadblocks works fine.

When set as occupant, IDF works fine except for a small script error [2] which happens sometime.

Script errors:
1. fn_createAIOutposts.sqf: _garrisonGroup undefined.
2. fn_NATOInit.sqf: _voice undefined, _regularvoices undefined.

whats your mod list?

My full mod list:
https://pastebin.com/HNv8sN47

Note:
Okay, I managed to somehow fix the garrisons not spawning. But, the problem now is that the attacks doesn't work. The vehicles do spawn, but they're empty. It seems that the problem was partially caused by mod order. This only fixed the garrison problem, not the empty attack vehicles.

Also, even after taking out all mods, the fn_NATOInit.sqf error still happens.

Edit:
Okay, I did more testing. I am now confused. Everything works fine in a new save file. But in my other save file, it's broken. Does it have anything to do with the war level? I'm going to investigate further.

Edit 2:
Did more testing. It seems like the bug only occurs in higher war levels, particularly above level 3. I don't understand why and how, but it happens to me both with and without my other mods.

Edit 3:
I was curious. I set both occupants and invaders as IDF. Both won't spawn. War level was 6 and I went to an IDF occupant outpost. It spawns. Next I went to an IDF invader outpost, it doesn't spawn. I went back to the same IDF occupant outpost before, no one spawns. I am utterly confused. Mind you, I only use the necessary mods for this, no additional mods.

I think maybe i found a small part of the issue, but im not sure
when i made the mod i didnt give the IDF voices because of the female identities
(chooses a random face and random voice from an array, so no way to assign females a feminine voice)
which could maybe explain
fn_NATOInit.sqf: _voice undefined, _regularvoices undefined.
Am working on an update that may or may not fix anything

fn_createAIOutposts.sqf: _garrisonGroup undefined.
This however i couldnt have less of a clue what the issue could be, Possibly an issue with Antistasi ultimate? as this mod was built for antistasi official and ultimate is built off of antistasi plus which is built off of official so maybe just too far removed from the original script

Thanks for the feedback! Unfortunately, I cannot play against IDF at the moment due to the bug. Any chance you make make one for the AU version? I understand if it's not something you want to do, but it'd be great if you make one. No pressure :D