10mil isn't over the odd's for a quality player, likewise he has no attitude problem. There is a difference between going out, getting blotto, hitting women, having women arrested in your house with coke on them.... and having Liverpool representatives tell you a deal is 99% done, telling your team mates, and being completely screwed.
AFAIK hasn't Jol said felt sorry for Dempsey as Liverpool screwed him and left him in a bad position, afaik Dempsey isn't refusing to train or anything, Jol just quite rightly wants to get the team he'll have long term playing as well as possible, which means, not relying or training with a guy who they think won't be there after August.
If Dempsey was english after last season he'd have been going for 20mil minimum, probably more, and probably still to Liverpool
That would be overvalued, 10mil is very good value. Cisse, Cabaye, Tiote were great value, not every deal will be epic value, good value is still good business, and the difference between Cabaye at 5mil untested in the league and 10mil for a player who is already known to be good in this league is basically nothing. The 5mil for Cabaye was significantly riskier than 10mil for Dempsey would be.
He is a great option for you though purely because what Newcastle want is quality, not quantity but you have such a high quality front three that a back up for each position of good enough quality that it wouldn't hurt the team too much would cost a lot, while Dempsey offers you striker/winger/playmaker roles and can play really anywhere in attack for one price and one wage. Good enough to rotate/rest any of the front three without comprimising the team, you can't really ask for more than that.
I don't think Newcastles entire season rests on the ACON, but it will certainly be easier to cope with if Ivory Coast beat Senegal
