Hello again! I would double-check the connections. Also, there is a (very small) switch at the top right of the board that will turn it on in case for some reason the primary power switch has failed. The switch that turns the blinking red lights on or off is to detect the chassis being open or not.
Finally, they need to create an official guide, but I believe that the steps in this post are what you need to follow to reset the newer mainboards: Reset forgotten BIOS password - #17 by sgilderd
Fingers crossed that one of the steps above work for you.