This is absolutely it. Worked in psych hospitals for a few years as a tech (think, glorified orderly), and I definitely have been given some of these notes to 'look over' by patients from time to time. Sometimes I'd build rapport with the patients and they'd write me little letters between shifts that were slightly more coherent but still really disorganized.

People tend to just associate this disorder with auditory and visual hallucinations or poor reality testing. These are definitely hallmark symptoms, but they're not the only symptoms. Disorganization is a huge identifier, especially when people form patterns from disorganized information. What we're seeing here is exactly that, a pattern that probably only made sense in the momentary context in which this person wrote it down. Show them the list three or four days later, and they would likely explain the pattern in a completely different way.