Dishwasher wedged-in can't remove to repair it

The builder has installed the dishwasher using unconventional and invisible fixings somewhere near the top of the appliance. There are no visible screws or fixings fixing through the cupboard either side, and it's not connected to the worktop that we can see or blocked by any flooring either. The Dishwasher's died and the repair engineer can't remove it - it wiggles at the base but is rigidly fixed at the top somehow. Builder's done a runner so we can't get him back.

Please kindly advise...

Dishwasher wedged-in can't remove to repair it