domain mapping or domain set up in mu

I’m sure there is a simple way to do this but I’ve been reading tutorials all day and racking my brain trying to get this to work so thought I would post.

I’m hosting on godaddy with the ultimate secure hosting plan.
I’ve got wordpress mu working correctly just as I want it:

for example testing it on :
https://www.tonymizzell.com (primary hosting account)

mu is working when I set up files for example:
https://www.tonymizzell.com/test
https://www.tonymizzell.com/tonymizzellnet
https://www.tonymizzell.com/tonymizzellorg

What I can’t get to work is making mu work for
https://www.tonymizzell.net
https://www.tonymizzell.org

I’ve installed the domain mapping plugin followed the directions and when I try to enable it it gives me the message to add a line of code to my wp config file and when I do that then everything crashes and I have to upload the original wp config file to get everything back in order.

I’m sure I’ve screwed up something in the database and don’t know what to delete out of there.

go daddy says for hosting the other domains that I have to add the domain under the primary domain for example:
tonymizzell.net with a directory of root/tonymizzellnet folder here.

Was hoping someone had experienced this and simple workaround that I can’t seem to resolve.

Thanks in Advance