Yeah, it makes a big difference when using these laptops that they are on a solid surface so as to not obstruct the vents...that causes serious overheating..along with dust/hairbuildup
There is one more long-shot you can try...Do a system restore back to a date prior to the drive not working...a month??? ...might do it..otherwise, sounds like the optical drive is toast...
If the manual says its a usb3 port then I would suggest thats what it is..as to why it looks different from other usb3 ports, you would have to go to the manufacturer for that one