I encountered an issue with the cable on my Reverb G2 not staying connected to the headset. This was my solution to:
1) keep the cable in place and keep the headset connected until I can complete a proper repair,
2) prevent the failure from happening again by preventing any cable pulling or tugging from applying any force to the connector. 

I have included .STL, and the zips for the .obj files. 

You will need several additional parts to complete this build;
m3 x 25 mm screw, x1
m3 x 7mm flat washer, x2
m3 x 8mm heat-set threaded insert
3mm x 25mm rod (can use M3 screw with nut)
Adhesive of Choice
Torch

I designed the holes a little small so I could work them into a friction fit, you may need to modify the parts slightly after printing. 

While printing the Anchor, pause the print at the top of the rectangular cavity in the center. Insert a washer into that cavity. It will be captured in the anchor. The threaded insert will butt up against this washer, and the washer will help prevent the screw from pulling the insert out of the anchor. 

The threaded insert will be inserted in the hole facing away from the lever arm. It should be set as deep as it will go, pressed all the way up to the embedded washer. 

The 3mm x 25mm rod serves as the axle between the anchor and the lever. This is a part I had laying around, you can use anything that will fit, and is stiff. The full width of the anchor is 27mm, the 25mm rod doesn't reach both ends. 

After printing, I had to work the screw hole in the lever open some, to allow the screw to pivot a little. It doesn't need a lot, it just needs to be able to rotate up and down a little to keep the screw straight as the lever moves. The last washer goes on the screw here to spread the clamping force across more of the lever's face. 

Finally, I had to adjust the front of the part to better contour to my headset. While testing and fitting for placement, I used a small torch to heat the brace that drops over the front of the headset. With it soft, I placed the anchor on the headset, taped it securely in place, and then let the anchor cool and set, conformed to the front curve of the headset. Then I marked placement. 

I used a small amount of super glue to secure the anchor to the headset and keep it in place. With the brace over the front, I don't expect the glue to handle the load of the clamp; rather, it's just there to ensure the anchor doesn't move side to side. I also intended to be able to break the glue joint, as this anchor prevents servicing the PCB; it holds the front cover in place.

As to placement of the anchor, I aligned it center-to-center with the plug, and pointed the sides of the anchor straight forward on the headset. This should clamp the plug straight into the connector, with minimal side forces.