I believe, based on what I've seen that Coyote territories overlap more/farther in, than what some believe. A visual; An irregular ring/mark, laying inside perhaps a 1/4 or more of another irregular ring/mark on a table top. Not just "touching" each other's outside border.
I've noticed these territories are very irregular. As for their "den site". It would be inside of their respective border, IMO.
I killed female from a pair, a few yrs ago. I was after this pr. I spotted them often laying in a small focal area, below a ridgeline on a hillside. I couldn't get close.
Finally, the snow went moderately soft. I stalked to a couple hundred yards from the them. I shot, missed the male, the female bolted quartering towards me, she died.
I hunted, that male heavily the rest of the Winter. Never seen him again. Infact, I didn't see a coyote track in that section the rest of that Winter. This section, had good habitat.
Following Winter, no tracks. Two Winters later, that section had coyotes in it again.