Glad I had the code for get-foggroups somewhere to be found. It looks like something weird happened to the get-foggroups function and all the code disappeared from it. I’ll need to get that fixed as soon as I can as that function is used all over the place. I have made an issue for it https://github.com/darksidemilk/FogApi/issues/3
I just published a new version of the module fixing the issue with get-foggroups and subsequently get-foggroupsbyname if you update to the new version 2103.2.12 those functions should work now.