"Sure, I had to precompute the answer and put it in lock boxes, but since he only gets to see one lockbox per run I don't have to make the lockboxes internally

"Sure, I had to precompute the answer and put it in lock boxes, but since he only gets to see one lockbox per run I don't have to make the lockboxes internally consistent, do I?" Yes you do. The lockboxes must be filled before Victor makes his choice, you cannot change their contents afterwards. Therefore, you cannot return the actual problem when he chooses that and 12345678 when he chooses a row or column. That would require changing the boxes after his choice. Also, if all rows contain 12345678 (same order), then columns contain 111111111, 222222222, ...., 999999999, not 12345678.