As per CCP rules, CCP will not add owners without consent from the original owner.
As this is an issue since the chat patch (March I believe) where only the owner can add/remove operators. If this owner isn’t playing anymore (sometimes up to 5 years) the alliance/corp isn’t able to moderate the channel anymore.
These channels may exist for many, many years and imbedded in lots of documentation.
These channels are normally obvious alliance/corp channels, not private player channels but channel to coordinate lots of different aligned alliances, for example intel channels (TheCitadel, anyone) or logi coordination channels.
These channels are part of the identity of these alliance/corporations.
-Recreation is not possible (not able to delete the channel)
-Contacting the original owner is not possible (we don’t know RL e-mail or phone numbers)
-Using a different channel name is out of the question (see identity/documentation)
My suggestion:
Make the current CEO of the owner’s corporation at the time the channel was created an extra owner, when requested by one of the operators in the channel.
If this is not possible it is (in my eyes) up to CCP to contact the AWOL person for consent, as the players cannot do this.