Upsetting story looking for a solution

Sorry to hear about your predicament. 

If I've learned anything from speaker listings here on Audiogon, it's that dented/poked tweeters have no negative effect on the sound and shouldn't keep you from listing them at what a non damaged pair would go for. /sarcasm

While going in from the back looks complicated, the side panels on the q5 look like it would give you somewhat easy access to the tweeter. Have you tried pulling off a side panel to see how hard a replacement would be? Could save you some money if you're handy.

Maybe I'm in a minority but I would be extremely unhappy to discover that a Q5 I purchased used had been "modified" by the previous owner. As I recall Magico spec even the torque to be applied to the bolts holding their cabinets together, even trying to take the thing apart risks scratches on the finish which again would materially affect resale. Given this is a current model and Magico offer great after sales service it seems insane to be DIY. Look at this as a fun time for your dealer to loan you some other speakers to enjoy while yours are back with Magico (and if you don't have this sort of close dealer relationship(s) at this level why not?)

Whatever you do I trust you will declare all this to any future buyer! Pity there's no CarFax for hi-fi

LOL

Pity there's no CarFax for hi-fi

Some of these units may do require sort-of title and "records of collision damage" :-0

 I am NOT selling. 

Interesting story- no child/pet should be nowhere near hifi gear, especially,
loudspeakers of this sort. Send the speakers back to Magico for proper repair.