To remotely control your camera with DSLR Remote via a Bluetooth connection, besides your smartphone/tablet and DSLR Remote, all you need is:
a camera with a connector for a cable release
a trigger cable for use with DSLR Remote, so a
a commercially available Bluetooth stereo headset.
No modification is needed on the headset whatsoever, it can be used as it is. Instructions on how to operate your camera via such a bluetooth connection you will find here.
|Example: LogiLink Bluetooth Stereo Headset V2.0 and a short cable with opto-couplers (LTV 352T)|