The two are very unlikely, nearly impossible to be directly related. I've had deep abdominal work done many, many times, and performed it frequently as well. The 'worst' that has happened was the escaping a of a bit of gas.
I've actually thought about this a few times, and flipped thru my pathology and physiology books {yeah I'm a big enough massage nerd I keep them close at hand in my room} The only thing I can come up with between those and personal experience/lecture notes is that deep abdominal work can release blockages in the stomach and intestines. So if she had liquid stool 'backed up' in her intestines, or was on medication that could cause same {regularly taking tylenol can do that in as little as 3 days of every 6 hour doses} then the abdominal work could have release the last bit of solid stool in her system, thereby 'making a path for' the liquid, as it were.
Barring medication combined with deep work however, I don't see how it could be possible. I'll post it to my peer board to be sure and let you know what the consensus is there [some of the people have been therapists for decades over there]
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