Yes, the right to erase is of course important, but that would be the right of both parties to erase their data in their PM's which of course they could each do without CM intervention, same as in an e-mail. Of course, things posted in public would be the admin's responsibility here, a third party which should not be privy to sensitive data hence why if people accidentally or deliberately post such stuff, we delete it asap often thanks to you guys reporting it sharpish!
In the case of the PAB, the T&C's here permit both parties to consensually supply information to MaxD the appointed arbitrator. This is only visible to him, not the other admin.
PM's are private too and cannot be seen this side unless somebody has deliberately and voluntarily shared it with the admin, say in the case of threats, attempted frauds etc. Then the admin has just cause to view the information as a concerned party of the business/entity.
I see no real difference, other than company policy or preference, why LV won't use PM. It's not being publicly posted after all.
I would have thought though that in a comparatively simple and straightforward issue like this that it would be reasonable to expect the function of the official rep of an accredited casino to assist, but there are no rules that specifically gauge the actual level of intervention required of a rep other than for them to log-in regularly and be responsive - in this case he has, even if only to pass the matter along the line.
Yes, it's not usual for a CM rep but if his company have this procedure established for these matters then he has to follow it, frustrating as it may be for the member here.