I'm not sure how long a massage at the GF takes, but I bought my dh the "King's Experience" for Christmas, and this is what the RPDE salesperson told me:
Dh should arrive 1/2 hour early for paperwork and fitting for the driver's suit. Then he will have class for 1 hour. Then he'll drive for 8 laps and go back in and get tips/critique from the instructor. Then back out and drive for 10 more laps.
So if your dh is doing the King's Experience, you should be able to drop him off, then have 1.5 hrs. before you'd need to be back to see him drive. Not sure if the Rookie Experience has the same 1 hr. class time, but it probably does. And I'm sure they all need the 1/2 hr. for paperwork/fitting. I don't know if 1.5 hrs. would be long enough to get to the GF, park, walk to the spa, undress, have the massage, dress, walk to the car, drive back to the speedway? Sounds like it might be pretty rushed if the massage lasts an hour; maybe if it was just a 1/2 hr. massage?
HTH,
Sue