As far as I can tell, this mod is released under the MIT license. However, there are two concerns I see with this.

First, the MIT license itself explicitly states the following:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

However, I wasn't able to find a copy of this license text in this repo.

Second, the MIT license expressly grants me permission to modify this software as I see fit, and publish those modifications as I see fit. Unfortunately, this is directly contradicted by some text in the Curseforge mod description:

Releasing modified builds to the public is NOT ALLOWED

As far as I can tell, attempting to add this restriction isn't compatible with the MIT license. The only option I can see here is to not use your software until the discrepancy is addressed.