He was making regular check-ins to friends via radio daily between 6 - 6.30pm.
Russell worked in the logging industry for some time and is familiar with the area.
The 74-year-old was last heard from on 20 March via HF radio where he advised he was having radio transmission issues.
Russell was confirmed to be at Wonnangatta Station in the Victorian Alps when he made the call.
Campers found Russell’s vehicle with signs of minor fire damage near Dry River Creek Trak at Billabong (Wonnangatta Valley) on 27 March.
Carol had told friends she was expecting to return home on 28 or 29 March and her car was parked in the garage at her residence.
Investigators have released images of Russell, Carol and a car similar in appearance to hers in the hope someone may have seen them and can provide information regarding their whereabouts.
It is not known what either of them are wearing and it is out of character for Russell not to make contact via the radio.
Police hold concerns for the welfare of Russell and Carol due to the amount of time they have been missing and Russell suffers from medical conditions.
Anyone with information is urged to contact Sale Police Station on 03 5142 2200.