I thought at first it might be going to be Curufin, but Celebrimbor makes even more sense! I had momentarily forgotten he would be already dead by the time Arwen was around. Nice to see her embarking on research like that!

I'm intrigued by the hint of possible further chapters.

(I can't spot anything wrong with the formatting.)

<i>Arwen brightened at the reminder that there would come a day when they would join their kin across the Sea, and have access to so much more information and sources than they did in the three hundredth year of the Third Age in Eriador.</i>

That was a sad little reminder of her sacrifice.

I wouldn't have expected Celebrimbor. I am wondering who I did suspect. Someone who wanted to take a wall city or castle. Seemed to me like Celebrimbor was always on the other side.

Initially, I wondered whether Arwen and Erestor suspected that Elros might have doodled on an old manuscript! XD Celebrimbor makes more sense though. Nice take on the prompt!

I didn't even realise it until Oshun pointed it out, but ouch, now I'm a bit sad that Arwen won't get to interview the suspects after all. It's only a tiny part of her sacrifice, but it all adds up...

This is very fun. I like that Elrond is making them do their own work. 

Ooh, I wasn't expecting Celebrimbor--that was a fun twist!