Getting back to the original post.

You have two options and, if your incoming flight is on schedule, you have the time for either one of them.

1/ use the arrivals lounge and walk landside from 2C to 2F2
This involves going twice through immigration, once upon arrival in 2C and once upon departure in 2F2. Immigration upon arrival can seem disorganized, but it hardly ever takes me more than 15mn to go through it (organized immigration queues in TBIT in LAX have taken up to 90mn of my time, so I'll take seemingly disorganized any time if it is three to six times shorter). Immigration check upon departure has never taken me more than 10mn.

Once you have cleared immigration in 2C, it should take you less than 5mn to reach the arrivals lounge. Is the lounge basic ? Well, there are 15 showers, I have never had to wait for one, and I find the overall experience pleasant, although it is neither an MB spa nor the Wing . The time needed to reach 2F2 immigration after leaving the arrivals lounge is about 10mn, via the Sheraton hotel, located above the TGV station. After both the immigration check and the security check for departing passengers in 2F2, you need less than 5mn to reach any departure gate.

2. remain outside the Schengen zone and take the airside shuttle from 2C to 2F2
This has taken me from 10mn to 30mn, depending on the arrival of the shuttle and its load. As this shuttle does not stop at Schengen terminals, there is only one 2F stop, which is the one you need to disembark at (2F2). You then need to clear security for connecting passengers (5-15mn) and you can then use the departures lounge which is located on the lower level, a the far end of the 2F2 peninsula. I believe there is only one shower in the business lounge, and the lounge itself can be very crowded.

Overall, I would recommend option 1.

Enjoy your flight