That might be your problem. You are not saying which top-of-the-line wireless gaming keyboard you have, but I have a "top-of-the-line" keyboard that costs as much as many whole computers, ($$!) and there are special modes that I could get into that alter the actions of what nearly all the keys do.
First, most of those special modes are only implemented, or even accessible, by you first installing the manufacturer's special keyboard driver software.
Second, you do not need any manufacturer's special keyboard driver to have the keyboard do the typical "I would expect" keyboard functions. Those functions are things like: typing any of the alphabetical characters, any of the numerical keys, using any of the F1 through F12 keys, or using the PrtScrn key, and a few others as well.
If you have installed some manufacturer's special keyboard driver software, just remove it and see if the PrtScrn key then acts like it is supposed to.
If that works, and I think it will, it just proves that the manufacturer's special keyboard driver software is either not working properly OR that you are getting into one of those modes that changes the PrtScrn key to do something else.
I would put my money on that last point.