I don't think that think that you'd have to get a different antenna for the Collin County layer.Correct, my Yagi is aimed at the Ridgeview tower. Tom's feed doesn't include metadata (that I can see). His feed does include Plano Dispatch 1, lagging a few minutes behind what I hear on my scanner.
The Yagi is not picking up the Collin County Simulcast, as its frequency range is specifically 800MHz/850MHz/900MHz/1700MHz/1800MHz/1900MHz/2100MHz/2600MHz. I've ordered a combiner which should arrive tomorrow so I can merge the discone signal with the Yagi. Since the Yagi is high gain/narrow band, I'm hoping its signal for Plano will be the one the scanner uses.
Looking at the page for the antenna, the frequency range, on the first line, includes 700MHz, even though that is not duplicated on the second line.

I think I'd try it before buying a second antenna.
Here's the map of sites for the Collin County side of PAWM. Looks like one of the sites is, sort of, "behind" the Ridgeview site you've aimed at for PAWM.
