This sounds bad on circumstantial evidence alone. Try asking a different RTG if this really was an RTG wide update. If you find the casino lied about the cause of the loss of connection, it is likely they could have done something to you.
RTG can do lots of things, they can alter the payouts of their games, and increase the number of decks in card games. It is possible to do this in a manner that is bad for the player, but to do so they have to disconnect the sessions of all players to make the alterations active, just as you sometimes have to reboot your PC after changing some software and windows features.
To further your case, how many spins did it take to eat your $4000 after the disconnect? If you were still betting high, the experience can still be down to bad luck, but if you were betting low ($1 or $2) and had the entire $4000 steadily eaten at around 10% payout, things would look bad for the casino. 3000 spins without a bonus also seems a bit odd, RTG bonus rounds are not as good as MG, and even 700+ spins without a bonus round on an MG slot is highly unlikely (it happens so rarely, that it warrants a post when it does as players feel something is wrong).
Empty Fruities Astern Capt'n
Back to port for unloading.
Full Sails - before we get raided ourselves.
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