They are all part of the Virtual group, and this is DELIBERATE POLICY, not a "misunderstanding" or "incompetence". Payment has to be dragged out of them, and even the very best experienced players know this can take MONTHS, and a great deal of time and effort.
They hope that many players will give up the pursuit, and walk away from the money. This leaves them with far fewer players who pursue the payment. Only the VERY persistent get paid in the end, and usually because it becomes MORE trouble for the group NOT to pay them.
Having messed a player around, they have already decided not to pay, as those they think are going to end up giving them even more money in the future are paid quickly, and without fuss.
You will have to convince them that rather than going away, you are going to press even HARDER the longer they take, and on top of which, you will "go public", or "seek legal advice" on the matter.
One player at Palace of Fat Chance had the whole forum community behind her, and it took THREE YEARS of persistent pressure and bad publicity before the group decided it was more trouble than it was worth to keep her money, and they finally paid up.
They know that this is quickly recouped from hapless victims like yourself, and if they eventually pay you, they will find other hapless victims from which to get the money.
This group are more "organised crime" than "rogue casino", they are VERY GOOD at scamming, and getting away with it, as they have had YEARS of practise in this dark art.
All we can do is seek to deprive them of further victims, and to this end, make sure EVERYBODY you know (and that you are happy to know that you play) hears this tale of non payment, and which casinos are to be avoided.
Where you see websites that carry glowing reviews of this lot, this is only because the webmaster is PAID, and quite handsomely, to carry these tributes. This is either through up front payments, or a considerable bounty paid for each hapless victim their site brings to the Virtual slaughterhouse.