For those asking, Krychowiak's release clause is actually 30 million Euros (21 million pounds). He's a top player and was the catalyst for Sevilla winning the Europa League last season. He's interception and tackling stats were phenomenal, and he actually scored a vital goal in the final against Dnipro. So, unlike Kramer, Bender, and others that are reliant on their home clubs wanting to cash in on them, there's no negotiation of a fee with Sevilla if we want Krychowiak. We'd have to convince the player to leave, but just like Milan did with Carlos Bacca (same release clause as Krychowiak), we'd be able to offer him a major salary raise.
I see several outlets like Goal and Sky Sports have pieces out mentioning N'Jie, but no mention of Lacazette getting injured in Lyon's match yesterday. If you want N'Jie, you'd better hope whatever happened to Lacazette isn't serious (it was his back he injured, it seems), because I can't imagine Lyon selling N'Jie with only 1 other proven striker in their squad. Injuries are the type of unforeseen things that can happen if you wait to buy players at the end of the transfer window.