I don't think it's anywhere near; DDG probably makes somewhere in the single digits millions per year, while Mozilla earns hundreds of millions from these deals.

As a comparison, DDG is serving about 10M searches/day. Google serves that amount every 5 seconds.

I don't know anything about the inner workings of DDG, but I'd have to assume $1m/yr would be a very large outgoing for them, never mind the $300m/yr of Google or $375m/yr of Yahoo.