Did the OP follow what William had suggested, even though the Lurker himself thought it was a long shot but seemed the only way to get it fixed...

Agree on the quick mattress run to get the most urgent thing taken care of first. Actually given it to me I would take the "insurance" first then tackle the mistake after that. Still dont understand how this would happen.

Both my SPG and Marriott have the same email address but luckily different password off just by one extra last digit. There were times I thought I logged in Marriott but found the details completely different even though it showed Marriott, yet the details were SPG's so I knew I logged in the wrong account.

Given OP's other Marriott account was an inactive one, wouldn't the account details would look so odd that it would bring alarm that this was not right, even though OP may not realize he had an inactive account - but wouldn't the account details looked so odd, that it would just give him a pause?