Comment 5 for bug 1909347

I have Ubuntu MATE on a VM and could reproduce your first issue there, i.e. it's present only when Neo 2 is not first in the list of keyboard layouts.

Consequently this is probably an xkeyboard-config issue and not specific to gnome-control-center. And the issue is reasonably upstream in nature.

I found this open upstream issue regarding Neo 2:

https://gitlab.freedesktop.org/xkeyboard-config/xkeyboard-config/-/issues/14

Can't tell if it's related to your observations. If not I would recommend you to file a new issue upstream. If you do, please post a link to it here for tracking purposes.