1st off, I love and use my Netduma XR5OO to the fullest. don't get it confuse.
For Warzone, I use geo-fencing. This gives me low ping WZ lobbies. Anyhow, I do get some sweats in these lobbies, and its no way around it in WZ. It depends on the time of day and what-not that you'll breeze through some lobbies like SBMM doesn't exist. 😁There isn't a certified way to get bot lobbies in WZ. Again, I use Netduma' geo fencing to compensate ping when I play WZ.
However, if you want true bot lobbies in Multiplayer like those famous phony Youtubers, I suggest you use YT' search engine. There's a few channels that tell or even show you how to get bot lobbies in multiplayer. I can tell you how to actually do it, but I don't think this is the right place to be showing actual steps on how to get bot lobbies in MW3. Anyway, good luck out there, and happy gaming.