We know from other passengers that united offered $400 and then $800 and a booking on the next flight.
The selection was not arbitrary, it followed United’s rules for selection. Your assertion that the selection “must be based on safety or security concerns.” is false. The DOT regulations do not require carriers to follow your assertion for selecting who gets bummped.
DOT regulations: https://www.transportation.gov/airconsumer/fly-rights#Overbooking
To quote from that source - “Airlines set their own “boarding priorities” — the order in which they will bump different categories of passengers in an oversale situation. When a flight is oversold and there are not enough volunteers, some airlines bump passengers with the lowest fares first. Others bump the last passengers to check in.”
I have decided to focus on the Easter Triduum. So my previous post was my last comment on the UA matter. I pray you and yours have a Blessed Easter.
I do hope you realize disagreeing with you implies no personal animosity on my part. If I have left you with any other impression I apologize.
Thanks.