To anyone reading this in 2024 and later - as six_montahue wrote above, I was able to resolve the initial issue of this thread (forcing a 5K2K monitor to output additional intermediary resolutions without hidpi loss) through use of the tool, BetterDisplay (new version of Better Dummy). Since this took about 1.5 hours of digging through random forums and Reddit threads, I created a short guide with screenshots to save time for anyone else who stumbles upon this thread. https://docs.google.com/document/d/1YcVmhAZuN-xP87NZ_LZogPI0c8ZsYCjP731z1aQf22k/edit?usp=sharing