Hi, as you can see from my profile, I have a lot of experience with Chrome Extensions.
I fully understand your project specification. Just to make it clear:
You want to be able to click on extension's button while visiting someone's LinkedIn profile, and after that extension should post an JSON containing all of the data you asked for to the previously set URL. And that URL, along with Auth Code can be set through Extension's Options menu.
I hope that's what you need, and I'd be glad to help you with your project.
Regards, Stefan