How can I create a GPX file from a .csv using writeOGR that preserves more attributes besides 'ele'. I need to include a timestamp for each point

Question

I have a csv file of locations and attributes (it's in a csv file because it was post-corrected from a TopCon GPS unit using NRCAN's PPP service).

I have columns for lat, lon, ele and time. I am now trying to make a GPX file from this csv. I am able to make a GPX but just cannot figure out how to preserve more attributes than just 'ele' for each point. I really need points to also have a time stamp. I have tried using GPS_USE_EXTENSIONS=YES but it appears to make no difference whatsoever to my output. I have also tried writing the GPX as a track, thinking it might then 'look' for a timestamp, with no success.

This is what my dataframe (df) looks like:

coordinates            ele          time
(-94.98907, 74.71942)  67.276       2014-07-11T01:46:36Z
(-94.98907, 74.71942)  67.282       2014-07-11T01:46:36Z

The weird looking time format is because that is what I eventually need it to look like in the GPX file.

Happy to provide the rest of the code (getting the spatial dataframe etc) if it's helpful.

Thank you in advance!