Does it have to add blame to the club, though? The "blame" could be on wrong and/or insufficient labeling of whatever product Sakho used. Or it could be a doctor and/or other person with expertise giving Sakho wrong advice.
The club will give dietary advice to him and also they will know the do's and don'ts for him. I dare say they will ask the players to declare any supplementary food stuffs that each player is taking, whilst also giving specific dietary advice. If he's stood up in the hearing and said " I told the club" what I was taking, then the club themselves will be culpable to an extent.
Lets not kid ourselves here - dietary recommendations on how the players nourish and re-hydrate themselves is a massive part of a players day to day. For him to go out of that, or the club to oversee that, is an indictment on either of them, or both.
Its a bitter pill to swallow(no pun intended) but he at the very least will receive a ban, if it moves on to the club, then who knows where that may end up.