[ He definitely notices the strange hand, he wants to remark something like "since when did Jack have a fake arm?" (he's assuming it goes further) but is momentarily distracted by the sudden info drop. ]

Se- seven years?!

Wai-wai-wai-wai-wait, you're telling me that Jack died seven years ago for you? And what am I going to rat you out for? Being the offbrand version of the universes worst monster? No one here will care.