Earlier today on Jenova, Aether DC there was minion withdrawal while attempting to spawn the S+. This incident was recorded.

https://www.youtube.com/watch?v=Z48LuaTKgV0

A player flees the minion, "Ker Shroud", and is subsequently targeted at random after for a spell, "Accursed Pox". However, the aoe from "Accursed Pox" needs to be centered on the player it has selected in order to start casting. It chases the player to try to accomplish this, (who had gone quite far by that point), and ends up tethering, immediately despawning and failing the S+ attempt.

It would be nice if SE revamped the idea of the S+ minions so that it is not so easily disrupted -a time limit is fine, but maybe don't make it disappear if it gets reset or tethers? As observed in Shadowbringers, the minions are easily exploited and can be despawned in order to troll, or accidentally in cases like these by people who are unaware of the circumstances regarding them and die or try to escape.

Disclaimer: This video is not intended to harass or belittle anyone who has accidentally caused a minion despawn. Accidents happen ^^ So let's fix the system instead.