yeah, just replace "Valmont" with x, whereas x stands for any person that fits the scheme.
I think her husband might actually be in a good position. Questions is whether or not Torrent could impersonate him well enough. On the other hand, in a rush of seconds, with her head somewhere else, she'll hardly be able to realize what's going on in a matter of seconds.
Where is he atm? We can't do this if he's around anywhere, or we'd risk having to Thorins running around. In that case, Commander Verres could do the trick, although I guess he wouldn't just appear out of thin air, if it really was him, but would arrive with more, well, uhm, presence, if you catch me.