When you send a course directly from Komoot to Connect the elevations are messed: maximum elevation is 12607 m. The same happens with other sources that use the Connect Courses API, so it is not a Komoot problem. Sending the same course to an Edge 25 doesn't result in the same error, the FIT file on the Edge 25 shows correct elevations.
Importing a GPX file with a track into the Connect app and sending it to the Edge Explore 2 goes well, elevations are correct. So it is a specific problem for the Edge Explore 2 in combination with the Courses API. Latest firmware version on the Edge, 24.21.