invented to keep out the cold
The most immediate thing she needs is to write another letter. In these matters, hours count. She should have before her guard shift, but that's the cost of testing her new spells.
Lhín writing, hired courier, shifted skin and (eventually, after a bit over an hour) a reasonable disguise...
To the Bank: Decipher and deliver the enclosed message to the House of Ornelos. Pay from my account.
For the Eyes of House Ornelos.
You know you have a problem with shipping deals. You will find Morgethai more willing to assist than you anticipate, and with more reserves for necessary investment.
That, unfortunately, is all the help she can offer here. House Ornelos should be as well informed as she is, but if it isn't, the first line should suffice to inform them there's an issue. From there, the rest should be obvious.
What she does know that they do not is that this was Morgethai-caused. (And that Morgethai now has at least her gold, as well as whatever she took from Ileosa.) Andoran doesn't like Cheliax in the best of times, but Morgethai's attention is a rare commodity. Cleaning up her own mess should pull her attention towards Korvosa, at least somewhat. What exactly can an archmage and an eighth circle wizard capable of calling a pit fiend do when working together? Tencednil has no idea. Almost certainly something useful, though. Archmages are said to have reshaped rivers, maybe they can make the Jeggare link to Lake Encarthan and immediately open up a completely new trade path to countries which would prefer Houses that are less Chelish or something absurd like that. Surely they have some options.
It might not work. If it does work, it might not be enough. But for now, it's all she can do.