If you believe any of the rubbish coming out of the Witsel camp you're naive. He's stalling to try and get other clubs and\or Juventus to come in for him and agree terms with Zenit. It's obvious.
Unless you believe what Witsel said about having loads of random people, claiming to be agents and trying to sell him to other clubs.
The only reason he hasn't rejected us is in case no one else comes in and agrees a fee with Zenit. He's probably trying to convince Zenit to accept the lower offer from Juve or get them to increase their offer.
The idea of an agent stalling a major transfer, against the wishes of his client, sounds beyond believable to me. He can just sack his agent if he dislikes what he's doing that much. If Juve increase their bid watch how long it'll take his transfer to complete. It'll be done within days imo and his agent won't have any contractual issues that need addressing, despite them offering his client worse terms. Strange that ...