You're allowed to use Don't Starve Alone for all categories including CC from what i can tell.

You might've misread the text in the category rules because I believe the rules for seeded runs make it quite clear to consult the list of approved mods as the definitive resource, there doesn't seem to be any mixed signals here:

"Runner must use a set seed for the world. Worlds may be seeded by editing worldgen_main.lua or via approved mods (check game rules for more information). Different seeds may be used for the surface and the caves if you wish."

Don't Starve Alone and Disable Autosave are currently the only two server mods allowed in every single category, and API Gem Core is allowed in all seeded categories.