02 Golf Antenna issue

I recently purchased a 02 Golf TDI that had an aftermarket radio in it that
just plain sucked. I purchased a used Premium 6 monsoon head unit with a
code and it almost works fine. The issue I'm having is with the antenna.

The original antenna cable is not the new farka style connector like the
radio is. I got an adapter for it. The radio will still barely pull in a
signal. I know the radio works because I have been using the FM transmitter
on my XM radio unit and it picks that up just fine.
I have also tried one of those adapters that puts out 12V on the center coax
for the amplified antenna and it still doesnt work. I did pull down the
headliner in the back and verified the coax back there is getting the 12V.
I do not know if the antenna itself is working.
I was wondering if there might be a problem with the coaxial impedance using
the adapter before I shell out the money for a new antenna.
Also, on the back of the head unit there are two different farka
connections. Which one is for what? The adapter only fits one of them.

Any other thoughts as to the problem are certainly welcome.