AMHash hasn't been running a ponzi.
So where did the payments in January/February come from? Certainly not from mining?
Of course they ran a ponzi for a couple of months, stop splitting hair. They paid customers' money back to them. It's irrelevant that they weren't signing up any new ones IN THAT PERIOD, if anything that just hastened the collapse. Don't forget that mining ponzis are not your classical investment ponzis - you don't have to pay back 120% or whatever, you can slowly bleed the suckers by paying back 90% of the initial investment and everyone will be happy - hey, it's mining, sometimes you don't get 100%+ ROI.
Now whether you want to hope they will rise from the dead and pay everyone back - that's another story. I hope for that too, I have a couple of BTC invested there unfortunately. I got paid back for the Prisma fiasco, which also looked quite hopeless but still far from this clusterfuck.
You have an incredibly loose definition of the term Ponzi. The hallmark of a Ponzi is that it takes in customer/investor money and does nothing with it but use it to pay back earlier investors. If AM took in money for 5PH/s worth of equipment and deployed 5PH/s of equipment, it does not make it a Ponzi if there is a service interruption and they pay customer dividends out of profits/reserves until such time as replacement hardware can be deployed. It just means there's a service interruption.
Now, if FC and/or the AMHash team does run off with all the equipment and coin, it's still not a Ponzi. It might be a theft or a scam, but that is a much broader category than a Ponzi. It would only really be a Ponzi if the entire farm was an elaborate sham, and they've been paying out customers from their own funds this whole time.