There would be nothing improper with your uncle reaching out to the Trustee's attny if there is one, or the Trustee if there is no attny. Better safe than sorry. Your uncle simply asks for an "open extension" to file an Answer pending approval of the settlement. Make sure that the response is in writing. Your uncle should also verify that once the settlement funds are paid the adversary will be dismissed - although I suspect there will be a dismissal provision in the settlement agreement;
I am sure this will work out for both of you but my comfort is in having something in writing.
Des.