I've now tried with 2 Macs, RasPi 3 and Win 10 x64 servers and could not get iPhone SE / 6 with iOS 10.3.2 to connect to the Mac's. RasPi 3 has your image downloaded yesterday (4th of July 2017).
Using the custom handler, onReset.$VENDOR_ID$.$PRODUCT_ID$=, but I still get "SURPRISE UNBIND" from the device and iPhone reboots when cable is disconnected.
When I start to use the problematic iPhones in the Win 10 x64, I can access the pictures on the phone OK (don't have iTunes on the Windows laptop).
With iPhone 6 iOS 10.1.1 there was no problem with connecting and using it in the Mac's.