Audio recorded at wrong sample rate

I had a similar problem I believe with a significantly smaller audio file size, but this is what I did.

I used an application called Handbrake which is a file conversion application to convert the originally sampled audio into a sample rate that I wanted to use and then used the original video file so there isn't any lag.

In my experience, sampling rate won't affect sync.  One second is one second.  No matter how many samples are in that second, PP will take one second to play it back.  Sampling rate only determines the upper frequencies of the recording.  (Half the sampling rate is the highest frequency you can capture.)

I've never had a problem mixing 48, 44.1 and even 32 sampling rates in the same sequence.

It's also my experience that poorly made audio recorders will drift even when the sampling rate matches, whereas a well made recorder won't drift.  I found the Zoom H4n well made, and am currently using the Zoom F4 without any sync issues even over 2 hour recordings.

Having said that, and having used some poorly made audio recorders that required attention, my habit was to line things up at the start of the clips, then adjust the speed of the audio until they also lined up at the end.

Audio drift is almost always impossible to avoid on long recordings since the internal clocks in each recording unit will have a small mismatch. Even if the recording was recorded at 48 kHz you would still have had some drifting of the audio.

When i cut music concerts i always cut with the audio from the camera/cameras and then sync the external audio to the first song and cut the audio then re-sync for each new song to get away from the drifting. It´s easy to mask those cuts with short audio transitions.