Mind control should count as capture.

[x_equals_speed]

Spent ages getting a Scylla down to its last 50 paralyse then was worried it would kill one of my guys so mind controlled it with the intention of free aiming darts into it next turn. Level ended without capture and overwrote my autosave.

If the level had carried on I'd have had no problems free aiming tranq darts into it until it was fully paralysed.

I get why you'd want to end a level when all enemies are mind controlled since it's not very interesting for the player to finish off an unresisting enemy, but if you're going to take control away and give a result on the basis of "You've got this, we'll just wrap it up for you" then you should assume that the player will do so competently.

Mind controlling the last enemy should result in kill rather than capture or at least the player should get the option not to have the level end.