Why don't you start a collective fund so that this guy takes one person and works on the case to it's conclusion. If he succeeds then you can get cheaper lawyers to do the light work of referring to the first case as a precedent (assuming that even applied).
This would make it easier on the pocketbook of customers and leave the lawyer with a less than fat wallet.
Quoting from
http://www.nolo.com/legal-encyclopedia/arbitration-basics-29947-2.html:
The arbitration decision.
Arbitrators are free to base their decisions on their own ideas of what is fair and just. Unlike judges, they are not required to follow the law or the reasoning of earlier case decisions.
So basically, we will have to present the same facts again and again, to new arbitrators in each case, who will make individual decisions.
We might win 80% and loose 20% of the cases, even if we are totally right.
I don't think we can spare the later cases by referring to precedents.
That being said, if HF realizes that it keeps loosing all the cases, they might settle the later ones, to spare the (futile) legal costs.