Help! My mission autocompletes upon entry!

As the subject line suggests, I've encountered a mission in an arc that I'm making that always autocompletes upon entry in test (and published) runs. It is in the Widow's Tower Unique Arachnos map. All custom enemy group containing only minions and lieutenants. 4 required objects, each are "Add an Ally" advanced goals. The captives are Black Scorpion, Ghost Widow, Mako, and Scirocco, all as lvl 50-52 AVs set to "do nothing" and "non combat." Each one has the guard mob set to "One" and the enemy group only contains one unit (this was the only method I could think of to pair up each signature AV with a specific custom enemy), which is a custom boss. When I enter the mission it completes and the guard mobs apparently do not spawn, as when I find each AV they say their "ally inactive" text. If for some reason the single-unit guard mobs are not spawning, that would complete all required objectives and the mission. What can I do to fix this?

There is no single-unit guard mob.
"Single" means the captive or ally does not have any guards.

There is no possibility currently to have a guarding mob be of an exact size (in your case 1), nor to have it contain exactly one of a certain special character.
The guarding mob will always scale with the difficulty setting and team size, and will contain several of your unique bosses when it scales up. If you add other characters to its group, it may contain, none, one, or still several depending on difficulty scale.

Furthermore, allies and captives with no guards left immediate count as completed, even if they never had guards. (Thus there also is no possibility currently to make finding someone without guards a mission requirement.)

You can only put your custom boss enemies in a boss fight detail and hope they spawn near the captive, or support the according suggestions to add exactly what you are looking for.

Ah, well thank you very much and I shall support this addition.