Garuda abilities softlock with Dread Mirror on maniac

[Nemesis]

As the title says, I used Dread Mirror and I couldn't cast any abilities nor transference. I cast Dread Mirror on a maniac on a very tight space (low ceiling, probably unable to stand or even get there by my own). Either the lock happened because the maniac disappeared as I cast Dread Mirror, was invulnerable once I cast it (I highly doubt that's the case) or when I hit him and the skill has to register it.