In the question https://video.stackexchange.com/questions/14529/sync-separate-audio-to-videobad-camera-audio-free-nle-recommendations I detailed how I manually did A/V sync for audio recorded separately from the video, with audacity and ffmpeg.

44.1kHz vs 48kHz has nothing to do with the drift.  The problem is that the camera's clock isn't exactly the same speed as the laptop's clock, so even though they both think they're recording 1 second per second, they drift relative to one another.  You need to stretch the video or the audio by 3 secs per 20mins, not just resample.