been following your travails on the yahoo group. the patience of Job comes to mind.
if you move the nuc, the bees will try to get back in the hive you took it off of. but if you move it one meter, and plug up the entrance of your Warré, they'll find the new spot a meter away. then you can open the Warré entrance when the proper nuc arrives.
as long as the first nuc is in the new spot and the Warré entrance is plugged for three days, everybody
should keep to themselves. if less time elapses, the first nuc bees may still try to get into the Warré. ultimately, that might not be a problem. it will be a little bit like a trap out, where foragers are allowed into another colony's hive because they're full of nectar or pollen, so they're clearly not robbing. you could end up with two nuc's worth of bees for the price of one.