[X] Use your momentum to push for a greater allowance for security forces and their support as well as more of their security infrastructure in the valley (+2 White Sky Favorability, -1 Ministry Favorability)
I think allowing the full retinue of Indigos is, frankly, a terrible idea - if only because the Imperials will demand to respond in kind. One sovereign per side, each with the role of protector, is relatively easy to manage, but a full court on either side at this very early stage will lead to many more points of potential high realm friction - which is the exact opposite of what we want.
Don't look just at the favourability numbers (though the exchange rate of option 3 is terrible regardless), please - these decisions will have extensive ramifications down the line. The White Sky have legitimate security concerns, but we cannot afford to station a hefty chunk of any given Count clan's upper echelons, when we'll have little control over who actually gets assigned. At best, this represents ceding an enormous amount of our own personal influence on the relationship (as well as CRX's), at worst it's a flashpoint and disaster in the making.
More broadly, the influence that absolutely must be maximised is of the actors with a direct stake in the proceedings, and their implementation along the border - that means the White Sky, the Emerald Seas (and its clans), and the White Plumes, who operate in the border area. The Polar Theocracy (PT) are their equivalent of our MoI - distant observers with very little actual stake in the execution. So long as we don't give either of these parties a reason to torpedo the talks (ie. negatives), what they think coming out the other side doesn't really matter - hence why I'm more than fine trading Ministry favourability for White Sky. 2 White Plume favourability - the spec ops forces operating in the Wall - for 1 Polar Theocracy - a distant observer - is an awful trade, and besides, wrangling their internal factions is frankly not our job, it's Jaromilas.