i need help figuring out what exactly these lines are and where they go, took my car to a shop and they were charging a crazy price for me to replace the intake manifold, they said these lines were dry rotted and cut them, if anyone could point me to a diagram or knows about this it would be appreciated

 

I don't see those lines you picture on my pre-facelift '04 R53 in that particular location.
It's hard for me to discern whether they are electrical wires or tubing. from the angle.
My first thought was it might be the windshield washer hoses. But they would run behind the plastic "firewall" and up along the upper right side inner hood area.
Judging by its location in your photo; If it is a wrapped wire(s) it could be the DRL/turn signal wire or to the horn (?)
It may also be the wire that connects to the wheel speed sensor.

It doesn't appear to me to be a vacuum line.
I just don't see those lines on my car in that location.

EDIT: In your photo - It does appear to be rubber where it was cut.
Do you think it may have once resembled this before it was cut? = circled in red in the photo below..