If your wiki posts are the OP then you could have your experts set the category to ‘Watching First Post’, and I believe that any edits to the wiki OP will then send out a notification.
Edit: Just tested that, and now I’m not so sure. 
I’ll try and dig out where I read it to see if I got confused.
Follow-up: I did indeed get a little confused. It seems that if you have the topic set to ‘Watching’ you get a notification every time the OP is edited. This would also send out a notification for every new reply in the topic too, so may not be ideal for your case.
The wiki author also gets a notification when the wiki is edited, so you could have the relevant expert be the poster of the OP and receive those.
There’s also the Data Explorer plug-in (depending on how you’re hosted), which can be used to create bespoke queries that you can share with moderators or custom groups to run on-demand.