He was quite destructed in both instances, if I'm right he'll know in pt/ mention it.
#distracted, sorry autocorrect text....
And this is where the disconnect is, because he wasn't distracted enough to describe the design that you are pointing to as the be all, end all proof they are the same blade (in BOTH circumstances)...but he
was distracted enough to not notice that very same similarity or even off-handedly comment how it looked like the blade he used to slit a man's throat. The whole book was him being angsty over the mantle and his actions, it fits right in for him to have a Vietnam flashback moment if he were holding the blade that killed Slate.
So you can't hold up the description on a pedestal and the reject that same description when he should clearly recognize it if it were Medea's Bodkin.