Hi Christian,
Interpolation between available waypoints can work if there are equal periods between events and if these events are in line. Otherwise, it will be pretty tricky to find an accurate position of the photo with interpolation. This is a feature to think about for Emlid Studio
David shared details of his setup in this post. The camera connects to the Reach M+ via the Hot Shoe. However, there was a need for isolation of the receiver. GNSS settings were also adjusted accordingly to our recommendations for Reach M+.