Does the file you attached include GAL details for the Gemini?
Nope, those files won't help you there.
If the GAL in that open spot is indeed needed I'd say there's not much I can do for you without another one of those which has the needed GAL in place to make a copy.
Seeing you've got the power connector on there though makes me wonder if you need a secondary power supply hooked up to get it to work at all.
Can you meter out if the VCC pins on the PDS connector are even connected to any components on the accelerator? On the Mercury there are several jumpers to select different power sources...
In the SE it would be obvious to have everything powered through the PDS connector. On the Plus you can choose to get power through the 68000 clip or an external power supply.
It's the same with Quik30 I got in my Classic which needs a secondary power supply to work at all as there is no power supplied to the accelerator through the clip that goes onto the logicboard CPU.