Should be a G280 CDI or G300 with the OM642 6cyl IL Turbo engine I believe, both are 3.0l and producing 183hp, no idea why the different codes for the same engine, maybe one was destined for the 6 x 6...presume you don’t have that?
You’re right, not a V6- the only other engine it had though was the OM612 which is 5IL642 is the V6.
That isn't a V6.