USB Type-C plug Eagle challenges

[frankb]

I want to use a USB-C plug in my design (Wurth 632712000112) and I want to get my board fabricated at a low-cost house (Seeedstudio / dirtyPCB).
The board needs to have this tiny "finger" protruding to meet a slot in the connector, to facilitate the insanely fine pins.

The first challenge is that the eagle models from Wurth don't have any information about the milling, so presumably, I can add the outline I highlighted to Layer 46.

The second challenge I have is the milling bit size. 0.3mm radius means a 0.6mm milling bit, wow!
From an email thread with Seeedstudio I was told to do the following:

Our standard milling tool diameter is 1mm so milling alone will not produce the internal radius needed. It is also very rare to find any sort of PCB milling tool below 0.5mm. I assume you have added 0.3mm drill holes on these spots to ensure the correct inner radius is met. We suggest adding an extra few to shape it out better.

The final challenge is to figure out how to fit this connector on the edge of a board, it appears I need to oversize the board outline to the end of the protrusion and then position the connector at the edge of the board and get the DRC yelling at me
.

If someone has advice please share it, if you just want to see my update thread as I burn my fingers on USB-C, keep watching...