You can change the level though. A +3 would simply be the max level its set to, so 20 in this instance plus 3. Level 23 mobs.
That would require them to rework all the existing lower level enemy types. Give them more abilities, so they're not just sitting there spamming level 1 powers in a level 50 tf 😞 .
Last mission of the task force had no AV, just a regular mob in the center of the room. Not sure if it was due to connectivity issues with the server prior to that mission. Or if the actual last mission is bugged and not spawning the AV. Lanaru The Mad wasn't there.
Edit: Just watched a stream of someone else running it, and the AV didn't spawn there aswell. So far two instances of it not working correctly.