I find your issue hard to understand..
Replacing a Wiikey with another Wiikey with the same firmware probably won't fix your problem I guess...
Anyway, replacing your modchip won't wreck your board.
Just be very gentle removing the chip, try to keep your solderpoints in shape.
I once pulled 3...
Since you can't reach the game menu's at all I suggest trying other backups you know worked before. If they don't run either you should try and update your firmware.
If they do, just burn another backup at 4x like reecarno stated and try again.
A little trail and error should do the trick...