From what I can tell, the 616 isn't necessarily newer, it's just from a C5 Audi A6 instead of a VW, but Audi steering wheels can have different functions and controls than what VW had from the era. It may not convert the resistance values the same to the data bus like the 451 does.
I would not assume they are interchangeable, but if you want to buy one and try it out anyway, would be interested in hearing what happens.