Sure, Shlemenko is a well-known fighter, but he's also been in 3 different organizations in his 3 fights before EFC, and that tells me that he's willing to fight for whoever makes a phone call.
I have watched some interviews with him, and his position is not to accept any offer, but "as he is experienced and his name is known, he accept only highly paid fights". He has told that he has lots of offers, but he expect to get paid 100k$ minimum.
Maybe he was not very honest in his interviews, but he is more interested to fight against someone who prefer striking over ground game. But if the money was the only that he was interested in, he could have accepted offer from Russian
Hardcore Fighting Championship. Its a bare knuckle fights, very popular in Russia. Even Alexander Emilianenko performed there recently. But to me this is more like reality tv show, as before fight, during talk show, fighters trash talk a lot.