No argument there, it's BS to bring guys here and pay them like that, and like hell they didn't know.
However, this case is not relevant to the H1B visa discussion, these were not workers here on H1B. This company brought a set of temp workers here to abuse them using much more lax L1 visas. Using that to describe the completely different H1B visas as similarly abusive is disingenuous.
As someone who works with H1B holders now and in the past, while many of them worked more hours than were reasonable, none of them were ignorant enough not to make prevailing wage here.