The biggest problem I see in this scenario, if I am understanding it correctly, is that your python was eating its second mouse in one feeding, which caused it a problem, and that it was doing so simply because you find it to be too challenging to drive for an entire twenty minutes to purchase an individual, more suitable rat. I do not perceive a problem with two mice being fed at once, per se, but simply in the fact that you appear to consistently take shortcuts in your keeping of your python, and alway look to expend as little energy and money as possible, and that, even in the smallest of ways, be they coincidence or not, your python is paying a price for this. As a further example of this, how do you feel about taking your python to a vet, so that all of your doubts about this (at least third) incident of bark swallowing could be placated? Do you find it sensible that an expert examining your animal, and thus having access to data, would be more likely to offer you accurate advice than would someone who can merely answer your question in a theoretical manner? Because, theoretically, your python should be "okay," if this is all you wish to know.

Aside from discussing the physiology of pythons and, specifically, their digestive system and how it would react to alien, non-food materials being ingested, what are your plans to discuss your personal approach to husbandry in a critical manner, and to soberly assess what I construe as being near-laziness and sloppiness, not to mention disregard for the ideal health of your animal? Will striving to do the most that you can for your python, as opposed to as little as is acceptable, ever be an issue for you?