I hope this doesnt come across as a know it all or being a a$$ but you are calling too much with coyote vocalization sounds. I spent a number of years trapping and killing coyotes professionally for the government. Not just a easy coyote here and there, but the coyotes that needed to be killed and killed now due to livestock predation. You need to understand something, Randy Anderson along with other people are in the business to sell their products. Do they show it working on You Tube or a tv show, sure, but do you know how many hours they filmed to get that sequence to make it look like it is the only way to get it done. I live in a country that is wide open and so I can see coyote behavior from a long ways off. The results you are getting are the results I would expect from the tactics you are using. How much barking are you hearing as compared to howling? We kill a lot of coyotes at 200 yards, and maybe your terrain and habitat dont allow for that long of a shot. However, that coyote is now at a distance where it needs to decide whether closing that distance is in its best interest. What is going to respond to a female invitation sequence ..... a single male that thinks he is tough enough to fight off any other competitors. Whats going to come to a mating sequence call ...... a male coyote that thinks he can drive off another male or a sexually confused coyote
. Most coyotes by this time of year are already paired up and unless their mate gets killed they arent actively pursuing another one.
Without knowing the lay of the land where you are calling or the amount of calling pressure you have in your area this might not be spot on, but maybe get you over the hump. See if you can locate a single coyote around sundown.
Set up to call in a spot where you are down wind of that coyote and have as much open area between you and the coyote as possible. Let your call make 1 or two female invitation howls. Then do not play your call again for 20 mins. No other sounds. Then if you feel there is still potential at the location repeat the invitation howl again and wait.
You are not going to get into a "conversation" with a E- caller and live coyotes and come out the winner. Coyote vocalizations are a lot more complex than that. Pup in distress during denning season is a good call to go to. Why dont you want to use a prey type sound?