Needing help identifying this component.

That engine is CM-870 almost identical to CM-871. The difference is -
870 Has air actuated turbo 871 Has electronic actuator on the turbo top
870 Emission control EGR only 871 EGR, DPF

 

Just know that with a CM-870/871 if the EGR has been deleted, most dealerships will turn you away as soon as they open the hood. If you don't have, or know of, a 'renegade'mechanic who is able to work on it...you're in for more hassle.

 

And the dealership knowingly told you that the egr has been deleted?

 

There are a lot of used truck dealers who are not licensed dealerships. That is to say, not licensed by the manufacturer. I purchased my '08 from a dealer, but Kenworth won't work on it because it's been modified.