She asks you for things she can use and not cheap crap. I don't know exactly how the game weighs things but I'm guessing it's a combination of the value and the goods themselves. The first time I ran the quest I gave her most of the recovery items in my inventory (other than Kaelirra's Tears) and a Camping Supplies and she accepted it. It worked out to about a quarter of what was being asked in coin. I just tested it again with lots of raw materials (borrowing a save from when I was stockpiling for the Wayfort upgrades) and tossed in some random tomes I had sitting in my inventory and that worked too.
There's a total value threshold of all the items you offer as tribute that you have to cross in order for her to accept the offer.