The hose connected to the air intake boot is also connected to the air distribution manifold that connects to the injectors. I believe it's to help atomize the fuel (you can search "air shrouded injectors". At any rate, having a crack at the intake boot is not a good thing, because you could introduce air that's not being metered by the MAF. Here's a link to the parts diagram:
https://www.etkbmw.com/bmw/EN/search...44/USA/13_1721 I'm going to say that the cable that deteriorated is for cruise control, since the other one is for the accelerator pedal.
The missing part? Have no idea - I have a '96ti basic, and I don't have anything in that spot either.
Paul
'96ti 238,800mi