very interesting .I am new to all this but find it very rewarding . One of my ball pythons seems to be a really good learner he is a male banana choco .I have a three year old rescue normal that at the moment is not really paying much attention . I have found feeding choco smaller meals more often means he is more receptive to following the target but he is also quite the adventurer.
My guess is that he will be more responsive with time. My boa gets quite excited when I approach his enclosure. I only feed him circa once a month. If he sees me as a cue, he should be able to understand a target. If conditioned to. FWIW, the excitement subdues when I let him smell my hand. I don't know how he reasons, but he at least get the hint that there's no food. Only me. He has no interest in me.
I find the whole study of snake behaviour & training fascinating. I was wondering if you have ever 'experimented' with smells? Apparently there are certain smells that either attract or repel snakes. And also training with sounds; apparently snakes can hear certain sounds or sound levels, and I remember a zoo trained their crocs (I know; different species) to react to the sound of a bell (the crocs would then move to an area where they could be weighed, and receive a treat afterwards).
Smells and sounds can be used as cues or enrichment. The smells or sounds chosen mush be able to be perceived by the animal and preference testing may need to be done initially to determine what they find reinforcing, neutral, or aversive.
That is flooding and not something we do here. Sacking out is much different than allowing the horses to investigate things on their own at their own pace. Forced interactions with objects or people should be avoided most of the time to ensure positive wellbeing for the horses or other animals.