Yeah, the opening without the doors on is about 2 inches narrower than what is advertised. I believe this is info coming from the manufacturer, so HD would be able to go back to them and recoup any loss.
We talked about selling it, but there’s still the problem of disassembly and transport.
Get a sawzall and enlarge the opening; use some pressure treated 2 x 4 or 4 x 4 lumber to reframe the inside door opening [use two galvanized or plastic post brackets to attach the posts to the concrete with concrete screws, and use roofing screws with plastic washers to reattach siding to new frame since your shed is resin. Or use liquid nails.] Get some wide trim boards to cover the cut edges on the outside to restore the door’s finished look, paint appropriately. Make some new doors, barn door style, and paint them a contrasting color.
As some one else said, consider this “tuition” for having to learn a hard lesson and woodworking “practice.”