Thosha During Megail's trip to Aran/Eustrin you write the following:
"With this you will miss out on 2 investments: Eustrin supplier (40k) and Aram supplier (20k). These are however not required to have Yhillin best battle outcomes. The Eustrin Embassy helps during the Ardford Summit (no extra unpeople) and for later choices."
However, the list of investments is stated here.
"Outside the Bounty Office, Aramite Supplier (20k)
Just west of the entrance to Eustrin: a dwarf near a shrine - Eustrin Embassy (100k)[11].
At the entrance of the Eustrin: the dwarf near the crate with the swords - Eustrin Manufacturer (25K from reserved funds).
The dwarf getting fooled by the little girl - Eustrin Processor (50k).
Pron remaining: 0k"
So we are now getting the Aramite Supplier? Why the change? It would seem that the player is only missing the Eustrin Supplier, with the Yhilin Supplier to be acquired just before the Ardford Summit.
Sorry, never-mind. The answer becomes obvious after studying the Investment page - Round 2: Megail's Route. The Yhilin Supplier is got later as noted. But the Aramite Supplier is unavailable if not purchased during Megail's trip to Eustrin.