I would like to think that any flight crew would NOT get involved in ANY dispute on the ground whilst preparing for their flight and not be expected to in any circumstances.
Those who think it a good idea to involve the crew in what may turn into a stressful situation prior to flight would do well to recall BE548.
Air travel used to be a fast way to travel, exciting, pleasurable and safe. We have lost most of that, lets not jeopardize the safety aspect.