I am no experet but not sure a clean B sample is proof the A sample was not tampered with.Waiting for the B sample results before drawing to any conclusions. I'm sure the players know it's ongoing and not to think the worst. Least it's finals and only 3 games max left for the next 6 months so hopefully we'll know before 2020 season.
Best case his B sample comes back next week clean and untampered and he still might be free to play in the Grand Final (if we make it). Maybe it was his first test and just freaked out and couldn't pee in front of someone looking at him and decided to try and put some liquid in there first (sweat, spit etc) as he couldn't pee then finally he was able to get past that anxious stage and was able to carry on his business as usual.