Nope, they can recall whatever they want; need to keep us buyers happy enough to come back for another if the problem(s) are that pervasive. My avalon has a sludging recall, no safety issue there when the engine just slags up!

Make the service guy take a ride with you to recreate it -- I wouldn't have left the parking lot without that. They are probably short staffed and figured if they could blow you off and you never come back, it's not a bad enough problem for them to take one of their workers away from somebody else's car repairs.

 

One of the techs did take a ride with me. Unfortunately I couldn't replicate the knock, mainly because there weren't any inclines around to go at an angle so that I could demonstrate it.
After I get back from my honeymoon in two weeks, i'm going to go back to the dealer and try once more and maybe take a longer ride with the tech. If they still can't find the problem, i'm going to have to start going to another dealer for service.
I would love to take the time to check it myself, but the problem is that I don't have a garage(only a driveway with limited space) and here in NJ it always seems to rain on my day off. This is also my DD so taking time to do work on it is a bit difficult to fit in with my schedule and not to mention all the wedding stuff in the past several weeks.