Why would you bill insurance for that and whose policy would you bill?
The audiologist should have set a fee with the attorneys prior to the meeting on a per hour basis to be reimbursed for the time it took to prepare for the meeting and for the actual meeting time involved.
Most professionals will set an agreement which includes a minimal amount of time for which they are to be reimbursed. For example, two hours of prep time at a certain rate and then a minimum of say two hours face to face discussion with a per hour fee for any time above two hours.
Also, you should include something about paying you a cancellation fee if they cancel the meeting at the last minute, especially if the expert had to cancel appointments to meet with the attorneys.
The attorneys are charging their client for their time in the meeting and the cost of an expert witness or speaking to an expert to gather information would be billed by them to their client.
From past experience doing this, get the agreement in writing prior to the meeting with the attorneys. If you don't, they're real good about finding a way not to pay you if they can get away with it.
Since this meeting already occurred, good luck getting the attorneys to pay you now.
Tom Cheezum, O.D., CPC