Fruit, veg and grains are considered Kosher. Lots of Jews eat non-Kosher meat so long as it's not pork, but it's a personal choice. Not all Jews are totally observant unless they're Orthodox or it's Passover, although obviously some are. I see no reason he should declare himself a Jew.

Why would he need to mention it? Why would it need to be shown in the HLs?

Simon: I'm Jewish
Other HM: Okay.

I do not think it is relevant what religion HM's are unless they bring it up.
Kinda seems like a non-issue.

Sums it up nicely.