Maury:
Thanks for your thoughtful post. I'm glad that I was able to provide a link for the path you have been following.
I don't know much about LANs, but would it be possible to have two HDHRs connected to the network to do what you want?
https://www.silicondust.com/
I understand your concern about signal loss in the coax, which is about 6 dB per 100 ft of RG6 for UHF. The traditional way to offset that loss is to mount a preamp near the antenna to amplify the signals before the coax attenuation. This only works if you don't have any very strong signals that would overload the preamp, which would create spurious signals in the preamp that would wipe out your weakest signals.
Looking at your TVFOOL report, it seems possible to add a preamp with moderate gain and resistance to overload near the antenna. In spite of the fact that the preamp will add its own noise to the signals, there is another benefit of the preamp which is to improve the total system Noise Figure. This is possible because a good preamp has a NF that is much less than the average ~7 dB NF of the tuner, and by the rules of cascaded NF math, the NF of the preamp primarily determines the total system NF because of its position at the beginning of the chain.
The result of the lower total system NF is greater sensitivity to weak signals. You can see examples of NF improvement here:
http://imageevent.com/holl_ands/files/ota
scroll down to and click on file 10 COMPARE System Noise Figures
With and Without Preamps
http://imageevent.com/holl_ands/file...=0&w=1&s=0&z=4
which was created by majortom of DHC. You can enter your own figures if you have Excel or OO Calc.
I also did an FM fool report based on your estimated location that shows some strong FM signals that could be attenuated by an FM filter to prevent interference with TV reception. See attachment. Roger1818 of DHC told me that the data for Canadian FM stations isn't up to date at FMFOOL.