XPS One 2710 Flicker

I am so grateful to find this forum, but at the same time so frustrated.  My computer is having the exact same issue as described here, and it is out of warranty.  I spent an hour on the phone with Dell yesterday, and because my computer passed all of the hardware diagnostics, the tech wanted me to pay for phone support to test all the software.

I asked him to read this forum....told him I knew what the issue was.  I told him I'd be willing to pay someone to install some sort of cooling device (I am a complete layperson and would be very scared to remove parts of my computer and implement some of the solutions I've read here), but he was not familiar with the issue and told me he had no way to read the forums (really???  I'm pretty sure he could type a link into a browser if he is a computer tech).

I have no doubt it is an overheating issue.  I found this forum in March when we had unseasonably warm temperatures in my area.  The issue went away when we went back to cold weather, and it's back now that it's hot outside again.  

Has anyone found a professional that has a solution that will not involve leaving the back of the computer open?  As I told Dell, I'd be more than happy to pay for someone to fix this.