Differential Vent cap install on 2010 E83 Help!!!

[skbmwx3]

Hello all,

I'm new to the BMW world with my new to me 2010 E83 3.0L. Love the vehicle the handling the comfort and that inline 6 are all buttery smooth.
But always a but, I've recently discovered an oil leak. I narrowed down the source to be from the front differential and it just so happens that the vent cap plug has come off. I purchased a new one from the dealership along with the appropriate oil to top up what had spewed out of the vent. I managed to top up the oil but the cap no such luck. Long story short, I spent the better part of a day getting my butt kicked by a $5 part in a really cramped spot. Anyone have any ideas of how to install this item without completely dismantling the car to do it? I had the front driver side tire removed for better access but this didn't make any difference. Access to the vent tube is near impossible I managed to get the vent cap positioned on top of the vent tube but couldn't get any leverage to push down on the cap to seat in place. see pics.

[BLKX3]

Can you get in there with something like 11 inch curved needle nose pliers?

[skbmwx3]

Yup thats how I got it positioned in place but could get any leverage to push down. Im starting to think that they supplied me with the wrong part. Id appears to be smaller than the od of the nipple.
Im going to call the dealership today to see if they will give me any assistance.