It looks like those are Tandy Benchmark and Mt. Minerva Hoyt, but Richard's explanation makes a lot of sense.
https://peakbagger.com/peak.aspx?pid=37076
https://peakbagger.com/peak.aspx?pid=34287
I noticed that nobody has searched Peak 5396, and there's only 1 trip report on Peakbagger: https://peakbagger.com/peak.aspx?pid=73994
I'm guessing a Verizon phone could ping the Serin tower from there even though it doesn't light up on the cell map, and it would be at less than 20% error of ping radius.