If the dispute has escalated and the Agent has been invited, neither a seller nor a buyer can cancel it.
This is done for 2 reasons:
a) to protect the Agent from false calls and
b) to make a fair decision on the buyer/seller’s case by a neutral third party.
Even if agreed, both a buyer and seller may still have disagreements over their case and decide to dispute again or escalate it. This back-and-forth process would take time and nerves on both sides.
It is also possible that a buyer accepts the seller’s replacement/edits just because he/she has little time to dispute and wait for new edits/products. Just like the seller may need a payment or maintain his/her reputation, and so decides to comply with the buyer’s new terms. In both cases, the two may still agree on new terms but at the expense of one of the parties.
This does not mean, that all disputed cases always result in Agent’s resolution.
Initially, disputes are decided by the two parties with no third party involved. More about the two separate options (simple dispute and Agent-assisted dispute) is here.