Re: Wrongly rejected interlaced modes from EDID?
There is a quite detailed article about EDID in Wikipedia. This answers your question about the native res (it is in the EDID but in a convoluted way and it seems unwise to rely on it for checks and calculations, see it as a hint only).
Many values are stored in the EDID in minimalist number of bits with tricky formulas.
This easily results in mistakes.
The real vertical refresh is PixelRate / (HTotal * VTotal).