Nethgul+Crystal Matrix: Can Nethgul Be Trusted?

[PyroStock]

Two 2N1E Enchantresses each with a Crystal Matrix. With 5 Communion Slaves I script them for Strength of Gaia, Earth Power & 3 simple Charms. I also give one Nethgul as I'm curious to see if he would gain the communion master bonus and cast higher level spells. I have a 3rd communion master, a crystal mage (2E2S).
They go through their 5 script spells fine. The enchantresses cast their 2 last scripted charms and then the enemy casts their spells, only Falling Frost & Nether Darts. No enemies or danger near them. The 5 communion slaves are at 103&104 fatigue. My casting round begins with that rainbow "8" icon going over all communion slaves & the enchantress with Nethgul. This enchantress and the 5 communion slaves are blinked to different parts of the battlefield. The enchantress with Nethgul blinks into the middle of the enemy army where she is prompty killed. Two communion slaves are also killed from their new unfortunate positioning.

What happened? The crystal mage didn't cast blink and he never moved, but even if he did it shouldn't blink another communion master. There was no global spell up. The other enchantress didn't blink. It didn't say Nethgul casted blink, but he seems to be the prime suspect. Was this blink caused specifically by combining Nethgul with a Crystal Matrix or can Nethgul decide to quietly blink his holder in any situation?