I think it will be a wasted vote if Lee and Casey are voted to go in there. Lee has already tried it on with Casey, been rebuffed (hence his late-night visit to the toilet to 'relieve' himself), lost interest in her and has now apparently moved on to Jasmine in his quest to play 'hide the sausage'.
If they do get voted in there, he'd probably try his luck again with Casey (in an 'any port in a storm' kind of way) and hopefully get rebuffed again, especially that Casey must realise by now she really is the booby prize (pun intended) as far as Lee's concerned, as he has said from the word go (and in front of Casey in the DR) that it's Jasmine he actually fancies and thinks is the best-looking.
I sincerely hope Casey has enough self-respect to tell him where to get off (ie in the toilet again) and that she is not prepared to play second fiddle to Jasmine.
I think it would be far more interesting to send either one of the other pairs in there, as it could possibly result in much the same outcome as it will with Lee and Casey, ie with one of each pair trying it on with the other (ie Nappy with Liz and Luisa with Evander), but I guess we'll never know, as it will undoubtedly be Lee and Casey who get voted in. (Yawn)