Dortmund did not hold firm though, the eventual fee was a good 10m off their original valuation
Not sure we're in a position to judge what Mahrez is doing. I remember earlier this season Leicester fans (and others as well) were heaping praise on him for staying with the club and playing out of his skin despite being denied his move to Roma which was pretty close to being finalised at some point - Leicesters valuation of his being the eventual reason it fell through. Now he sees another CL club coming in for him and after the praise he's got and the performances he's put in he again is denied by the club
It's understandable as it was way too late in the window and LC are entitled to look out for the club's interest first, his departure would've seriously derailed their season. At the same time he's right to feel hard done by as he most likely will have heard promises from the club that the next club with a reasonable offer will be listened to
His salary at Leicester does not come into this at all. That's money the club only has because of his performances over the last three years, he's entitled to it 100% even if he throws a tantrum to leave