I don't know if this will or can help with your specific Tonneau Cover, but it worked for me with little modification on one of my older Tonneau Covers, which was 12 years old and long out of production for parts.
I looked at all the Tonneau Cover companies websites and found the securing clips that looked the most like what was on my old one. I ordered from them as the Security Clips are pretty much similar in function because they all attach to the same rail that's part of the bed.
There were two holes predrilled into the clip for screws to attach to the Tonneau Cover. Once I lined everything up for it to function on my old Tonneau cover, I found I only had to put a small shim in place under the clip and drill out only one new screw hole to line up with the existing holes on the frame of the Tonneau cover.
I worked perfectly for another several years.
Hope that helps.