That is not quite the way it works.
I have big credit lines like that. Some casinos will temp close my lines after I win and cash out (they don't care if I win, hold the chips or deposit the chips - only cashing out triggers the temp closure). By temp close I mean - close for anywhere from 3 to max 7 days. After that period of time has passed, "it is a whole new ball game" and the line automatically reopens.
But there are casinos that, by special arrangement, will allow me to cash out any sum and not temp close my line.
And then also even casinos that do temp close lines do not always do it, it may depend on the amount of win weighed against the size of the line, and prior win/loss history.
My lines are permanent (not trip to trip) and permanent lines are the norm - I assume Leforbes' line too was permanent.
So, to say that Fontainebleu "screwed up" by not closing his line after he cashed out a big win - maybe. Maybe he had an arrangement with them, as I do, to never close his line no matter how much he cashes out. And in any case, at worst they would have temp closed his line for 3 - 7 days, after which he could have returned and blown through it anyway.
There I might agree with you. There must have been some overriding reason why the casino didn't get too aggressive with collection efforts.
And when a marker, especially a large one, is defaulted on and not turned over to the DA Bad Check Unit, there is usually a reason. There are well known cases where for whatever reason the casino simply sued over the markers and never turned the matter over to the DA. For example markers from Brandon "Greasy Bear" Davis, or Girls Gone Wild founder Joe Francis. Those two or at least Francis claimed some kind of extortion from the casino (in Francis' case Wynn) to pay the debt under threat of death. In other words, somehow, these debtors and other debtors like them somehow muddied the water enough such that the casinos decided to sue versus pursue the criminal route. Or perhaps the casinos just didn't want the bad publicity of threatening to jail celebrities or celebrity types over markers. Or maybe the casino held onto the markers for too long hoping theses guys would pay and by then the markers appeared too much like long term notes versus immediately payable checks such that the criminal case had been weakened.
If you look at the history of publicized DA bad check cases in Vegas, it would seem like the casinos don't care who the debtor is, they will seek prosecution. But there are notable exceptions.