I think this question had been ask a few times before , there are a lot of old thread which over 100 pages.
1.Thread starter user MIA , can't contact and no update on 1st post
2.Some post require modification and some user spam and should be delete but TS MIA

In this condition , is it possible to have an extra user or mod function for 2nd active user to moderate the thread ?

Beside moderator , Only TS can modified/update 1st post and delete post from spam or unrelated topic.
Even someone would like to take in charge the topic thread but unable to do so.Close the thread also require TS.Any suggestion beside creating an extra Thread.

Possible to add in an extra function to modified post after passing the poll to selecting new TS ?

Should include reminder after polling done to remind TS that another user will be added into the TS criteria

That way, if there is any credits from OG TS, then it will be remarked; whilst also giving the original TS a chance to choose whether to continue contributing or not

While accounts that have been suspended / deactivated / inactive for more than a certain periods of time, can be also remarked as such

Whereas the polling feature can only be initiated for last edits more than 5 years > 3 years > 1 years etc?