According to Mitztah https://www.swgemu.com/forums/showthr...=1#post1284013 all missing vendors are gone and not coming back, so no you do not need to worry about anything "timing out" on them - its already gone.
According to TA https://www.swgemu.com/forums/showthr...=1#post1280160 He has a backup database with the missing vendors and will attempt to retrieve the items from the missing vendors and allow owners to go somewhere and get their missing stuff. Even if timers still existed on the missing (gone, deleted, never coming back) vendors, it still wouldn't matter since TA will be working from a backup database, not a current one being affected by timers.