Best pursue the matter of constantly being disconnected by the operator. Try contacting them, but omit the reference number and see if the "error" of being disconnected still occurs. If not, mention to the operator that you constantly get disconnected, and could they phone you right now on a "call back".
If they put the phone down on you it will be a lot harder for them to blame the software or the internet connection.
If casinos start bouncing checks, and then appearing to treat the payees rudely when they complain, they deserve to suffer the consequences of loss of confidence from players.
I think Grand Monaco is accredited here, so a
PAB is an option. If they are members of eCogra, this would be another. The more valid complaints eCogra get about problems paying US players (while happily accepting their deposits) the better to force honesty and transparency on the situation. Players can then be fully aware of the risks should they WIN, let alone the known risks of losing.