obviously, you have either trapped this by now, or decided to let it go..
big pastures are perfect spots for footholds-
Look first to any high points, cut banks, etc. A high spot might just be inches higher than the surrounding area, but it makes a difference.
and in a big pasture with short grass (grazed) you are going to have cow trails and 2 tracks. check out the main intersections- a couple of dirt holes under a sage or yucca on an elevated point near at this intersection will be very productive.
Use whatever visuals you have- a big rib bone for example with a couple of sets near it, will pull coyotes a long ways.
any badger diggings, gophers or PD diggings are also must spots to look and most likely set up.
remember that in a "featureless" area- ANY structure, feature will be a point.
look at the flow- along "color" lines (different textures grasses, colors, density, etc)- I often make setso n2 shades of grass in new/old hay plantings. Even if the grass is 100% the same grass, heighth, etc- they follow it for long distances.
When everything else fails for location- look for the prominent habitat areas that you CAN SEE- they don't have to be close by- and set up the line from A to B- remember that coyotes in this type of location, will "flow" following the easiest path more times than not.