"The Wolfenstein Challenge" - "The Trap" [2nd campaign, 2nd mission]

Hello everyone! Could you please tell me how long it should take for this Andreas to appear? My army is already super strong, and a lot of time has passed since I completed the quests; I've been playing for three months now, but he still hasn't shown up! Maybe it's a bug; has anyone else experienced this? Should I restart the game, or is there another solution? The disc is a licensed copy, and everything seems to be working fine! I've been playing for a while, but this is the first time this has happened... :confused: