I'm trying to remember why this part was ruled out.
https://media.digikey.com/pdf/Data%20Sheets/MegaChips%20PDFs/STDP2600_DS.pdf
It seems like it could be a good solution. Generate DVI and SPDIF into the STDP2600 and get Display port out the other side. Then leave it to the user to use a converter to VGA, HDMI, DVI, etc.