I put a piece of cloth over a prybar and stuck that under the hatch, with a small weight hanging off it.
Then I cycled power to the hatch, it' unlatched for a moment, and the prybar lifted it open.
After that, I set an old work glove over the latch, so that it could accidently lock closed again.
And yes, I did pull the big orange safety disconnect. Here it is, see?
