I've got a potential bump plugin if some wants to test it, you can let me know in this discussion.
It updates the DateLastComment Field to current time when bump is clicked without adding a bump comment.
I don't think this will have any impact other than to cause discussion to rise, but if someone has some caveats against doing this, let me know.
It will allow people with permission to bump to cause discussion to rise. Probably best for mods and admins so it is not abused.
I may not provide the completed solution you might desire, but I do try to provide honest suggestions to help you solve your issue.