I own a middle aged female mini foxie (pictured in avatar), who has always been quite wilful and has a dominant personality, only being submissive to me and my wife.
I spend a lot of time working in parkland exercising groups of dogs, so she spends most of her day off leash. I've managed to train her in recall so she reliably returns about 95% of the time through only rewarding her with food when she comes back the first time I call, and by praising her but giving her no food reward if she makes me wait. It's been challenging but she's pretty good most of the time, snapping to attention as soon as she hears my voice, and she is very motivated by food as she is basically a bin with legs. She has had multiple other behavioural problems stemming from being locked in a filthy cat hoarder's house before I adopted her. When I got her I had to teach her normal dog behaviour such as how to play nicely, how to interact with other dogs, toilet training, how to dig, how to follow a scent, etc. I've managed to eliminate behaviours like incessant barking and whining, and harassing other dogs and she is now my obedient, well socialised little friend.
However I seem to have hit a wall in her training, as very occasionally she is extremely disobedient - she decides that whatever she is doing is more important than what I am telling her to do, sometimes requiring me to go and remove her from whatever she is doing. This isn't much of a problem when she's found a dead possum or cat spoor as she will return once she's finished with it within 1 or 2 minutes, but a lot of the time this is caused by some well-meaning person patting her and even giving her food while I am calling and whistling for her. This is not acceptable as I need all the dogs under my care to stay together in their group for safety. If nothing else it sets a bad example.
This is frustrating because I'm not sure how to proceed - she has a very extroverted, friendly, celebrity-type personality and loves getting attention from everyone, especially people she hasn't met before. I don't mind her socializing with strangers within reason but she is obviously learning that she can still get rewarded by these strangers for being very disobedient. How do I handle this?
I thought about using raw mince as an emergency reward for these situations, to make my reward better than the strangers' reward of attention, and to condition her to return to me when being patted by a stranger, but usually she is so far away that she can't smell it. Like I said, 95% of the time she is very obedient, but the 5% of the time she decides to be disobedient is turning out to be a real problem for me as she is often out of my line of sight. The people patting and feeding her don't seem to care that she is being called away, assumedly because they are mesmerised by her prancing cuteness. Does anyone know how I should continue her training to make her recall even more reliable?
Any help or insight would be greatly appreciated.
[TL;DR: My dog's recall isn't 100% reliable, pls help.]