Common definitions of an organ, Webster:
> a. differentiated structure (such as a heart, kidney, leaf, or stem) consisting of cells and tissues and performing some specific function in an organism.
> b. bodily parts performing a function or cooperating in an activity the eyes and related structures that make up the visual organs.
Wikipedia:
> Organs are collections of tissues with a similar function.
Britannica:
> a group of tissues in a living organism that have been adapted to perform a specific function.
Oxford:
> part of an organism which is typically self-contained and has a specific vital function.
These newly discovered channels, do not seem to consist of either cells or tissues and does not appear to be self-contained. I just feel like the authors thought, "if we say it might be a new organ we'll get bigger headlines."