Every single team with someone past their peak like Dier will be linked this summer.
I really, really hope it's true. But, it's probably not, unless the 'Dier is fighting for his place' PR was a price-raising tactic. Would only seem to affect his wages, though, rather than a fee.
Side note: Jesus, I've just seen Dier's missus... Man, he is a lucky, lucky boy.