Have them show you exactly what they did. You want to know where the Kicker tweeters are wired to in particular. They should be able to show you with the door panel off. Namely, if the Kicker tweeters are hooked to the MBQ crossover or to their own spot on the amp. It should be the second way. I'm not sure if I can actually solve anyting, but we can sure try.

I'm not a fan of adding additional tweeters to a setup, expecially tweeters that are not identical to (let alone a different brand entirely) the main set being used. You wouldn't do that with your HT now, would you?

Since the 216's are components, you can take the MBQ tweeter and put them up in the A-pillar or dash, away from the mid if you like. I prefer to have them together, even though the stage may be a little low, but many people do like the height. It's personal preference. I think you'd be much better off going this route. Try to find a spot where the distance from the mid to you and the distance from that tweeter to you are the same and it should help minimize the difference.