No worries. Categories can be overlooked when you're searching.
Unfortunately there really isn't anything more than can be achieved. In your case, the Fire OS is responsible for drawing and placing the window; Channels has no idea where that window will be placed, so it cannot change its layout to adapt to where the PiP window is placed. (I believe most systems will allow you to move the window to different corners; this may be an option for you to shuffle the window out of the way so you can better see the content on the screen.)
Since this is the Apple TV section, it might interest you to know that the PiP window on that device will move out of the if the focused item will be covered by the window. For instance, if the window is in the lower right, and you are scrolling to the right on the last row of the guide, the window will move slightly up allowing the entire cell of the guide to be read.