I have the Solex geotagging add-on. I love Solex for free flight, missions not so much and the geotagging workflow is clunky at best. Just give me a tlog and it's so simple with a variety of other tools/GCS. I've got 20-30 students a semester learning data acquisition and I use Solex for flight training and at one time hoped that it would work for missions as well...but it doesn't. Asking an undergrad to geotag using Solex is like asking them build a spaceship out of a pen cap.
Here's what I would do.
Use either Wookiee or WinSCP to grab the tlogs and like you are probably already doing use Mission Planner to Geo reference images.
Or grab the Solo metadata by using the scripts here. You might have to do a little tweaking of the data/scripts but that's what students are for.