Printer doesn't like tall things?

So my lab group has a Taz 6 that we use for prototyping. Most of the time it works great, but for one part, we cannot get it to print. It’s a long, nearly 7", print, and thin, about a half inch in either direction (see image for CAD model). I have a couple of images representative of how it fails, and generally it fails around the same part of the print, up higher as shown in one of the images below, though not always, as shown in the other image. It’s printing in PLA using the Cura software, and we’ve tried 5% infill and high speed setting as well as 100% infill and high detail, as well as a few in-between and mix-and-match of those, all with the pre-set temperature settings. One print has worked, but we couldn’t duplicate it. The prints have either been with a skirt or a brim, though it hasn’t been consistent as to which, with support generated.

Regarding the part: it’s a thin-walled rectangular tube that’s capped at one end and open at the other with 7 identical holes down the length of the front face.

EDIT: The attachment process for this forum is very silly.
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ben_0618_1.gcode (1.39 MB)
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