Alright. To caveat off of my previous posts.
MM's will be held responsible for any and all wipes that occur. This is to prevent scams where the MM claims they were wiped, when in reality, they were not. This is merely a precaution.
IF the participants in the trade wish. I personally see no harm in an agreement between the 3 parties (Buyer, Seller, and MM) that exempts the MM from responsibility of a wipe. This will be purely a case-by-case basis, and will NOT be accepted in a MM's ToS. Don't even try.
Buyer, Seller, and MM MUST agree (and have screenshot evidence) of such an agreement. In this case and in this case ONLY will the MM be "pardoned" per se for a wipe if it were to happen.
Also - In response to TBT's post. If you're recording, and the reset takes place DURING THE TRADE, and DURING the recording (ex. You're booted off the account. You log back in, and the RSGP/item(s) are gone) - Exceptions may be made in this case.