It is possible to download track in a GPX file and shift all times.
I did same procedure by GPS track Editor.
0. Download both tracks only one will be changed. The second is for reference.
1. Open both tracks in “GPS track Editor” application
2. Find a stating point in space. Both track were at similar location.
3. calculate the time diff between tracks at that point in space.
4. Shift time to one of track by Track | Time | Shift tool.
5. Save corrected file
6. Import time shifted track to RaceQs as different skipper in order to prevent overwrite your original track.