This is all rather confusing and I do wonder if it's an attempt by his lawyers and UEFA to find a way to let the host nation play him in the Euros (they have a couple of injuries at centre back I believe) before a lengthy ban.
Now before someone kindly subscribes me up to Tin Foil Hat monthly let's follow the logic based on what we seem to know:
There is a substance that is on the banned list.
As a professional footballer Mamo is supposed to check the list and inform the club as to what he is taking.
He doesn't inform the club, and presumably he doesn't inform WADA or UEFA there is a mistake with their lists.
Mamo takes the substance.
He fails a drug test.
He doesn't send a B sample and voluntarily sits out a game or 2.
UEFA suspend him pending hearing, presuming guilt and preventing his playing for his club and country.
Mamo's Lawyers presumably bring up the defence that the drug shouldn't be on the list.
UEFA do not extend the suspension, presuming innocence, allowing him to play for France in the Euros, while they check.
How long does it take to check? One phone call. Hey WADA, is substance X meant to be on the list, or was it a typo?
I fear UEFA is doing the hosts a favour by the delay and Liverpool will be the ones to bear the brunt.
That said, I hope something new turns up such as he was taking Substance Y which is not on the list but which gives a false positive for Substance X which is on the list.