CRS
Keep it simple, the RAD NAV input field is labeled CRS, that is the abbreviation for COURSE.
Technically speaking, flying course 090 to the VOR is indeed flying Radial 270 inbound.
Imagine an approach on course 090 to the VOR, but the VOR station is located 2 miles in front of the runway. While inbound on 090, you are on the 270 radial flying inbound, after passing overhead the beacon, al off a sudden you are flying the 090 radial outbound. Does your friend recommend that overhead the beacon you have to quickly adjust your RAD NAV entry?
Your friend may be mixing up the situation with an intercept leg, there the system asks whether you want to intercept the "radial" inbound to or outbound from the point. (used the quotation mark because such a "radial" can be drawn based on any waypoint, not just VOR beacons).
The CRS input into the RADNAV page has nothing to do with accuracy, but with proper orientation of the head and tail of the needle, to/from indication and sense of the deviation indication.