Qualins Rachmirol: 1d20+1 = 2
Qualins Rachmirol is an adventurer, and a skilled one.
Adventurers like her don't own houses. They don't have servants. They try very very hard not to pay taxes. Adventurers tend to carry a rather significant fraction of their net worth on their person in the form of weapons and magic items. When choosing how to spend their marginal 2000gp, "equip an entire Watch Patrol with masterwork weapons" doesn't exist as an option to compare with "buy a +1 weapon because I deserve nice things."
(Instead the options to weigh look more like "enchant my armor and my shield with +1 enhancement bonuses for 1000 gp each, increasing my AC by 2 and decreasing my chance of taking any damage from an attack by ten percentage points, or enchant my weapon with +1, which increases my chance of hitting with an attack by (checks math, takes note that (comparatively) cheap 300gp masterwork weapons already give an enhancement bonus to hit and that enhancement bonuses don't stack...) precisely fuck all. And increases my damage per hit by 1. Just... increases it by one single point of damage." (No one ever buys a +1 weapon for 2000gp, they wait until they have 8000 saved and buy a +2 or equivalent. For rare emergencies where they desperately need to bypass DR magic or affect an incorporeal creature, they use a 50gp oil of magic weapon.))
Vault Colonel Qualins Rachmirol is neither the richest person in the room, nor the highest level.
But after Togomor (himself a solo operator), she probably is carrying the most magic swag.
Whichever side of the fight she joins will gain substantially thereby.
Rachmirol isn't a complete outsider to the City of Korvosa. But it's not where she was born or grew up. She's fond of the Korvosan Guard in general and Cressida Kroft in particular, both of whom take pains to treat adventurers right. If it were clear to her who knocked the Field Marshall down, that'd be the person she'd jump.
But it isn't clear, so she'll draw a magic sword and move to support Queen Ileosa and her little group of defenders.
Call it chivalry.
Ileosa called her pretty, so now she has to return the favor by keeping her from harm. Besides, (the Vault Colonel feels) the Queen's done a pretty good job so far. She seems to have her head on straight when she isn't flailingly trying to defend herself from one of her enemies.