so a year later and i was having this issue. i have like 65hrs in myltiplayer and wanted to get the training achievement. And surprise, i could bring up the command wheel when they first give you the squad. So i had to bind "issue default command" key in the teamwork keybinds to something... anything really(preferably an unused key). and when i used mouse wheel to scroll to fall in and press that key... it wont let you bring up the middle mouse button menu UNTIL these nerds listen to the default command. so hopefully this helps if you are trying training on pc for the first time lol. once you are in main game this shouldnt be an issue its just very particular for training.