yes you can recover them.
A mate had a fault on his car that drained the Westco AGM battery (same type as the Odyssey). Initially his intelligent charger said the battery was dead. I suggested he connect another battery in parallel to the Westco and restart the charger.
This time the charger went through the initial test and started to charge the battery. After a minute or two the parallel battery was disconnected and, quite some time later, the Westco was fully charged.