Four.

One believes this "Iridescent queen" is quite likely to be crossed anyhow as, if one read the narrative without mistake so far, she is the smae as 'Biru' and the goal of the client 'Aubrey' appears to be to free her friends currently kept as precious resources by the so called 'Masters' under her comand.
One does expect the person who we are out to rob will end up as rather unfriendly one way or another.

However there is the a valid concern that an outcast presence might make her more.. conspicuous but given "Aubrey" nature as a material and non native of the so called "in between" layer, this is a somewhat moot point. And the knowlege and afinity to the "in between"

The last issue is 'trust'. Our alliance with "the esteemed Rahasya" should be kept on purely utilitarian terms To quote from another narrative: "The enemy of my enemy.. is the enemy of my enemy, no more no less.".

it is clear she doesn not sonsider our primary client of the same status as her. Even if one is not quite familiar with the politics of the "In between" layer, one might suspect an outcast could be tempted to regain the favor of the irdecent queen by say, selling her a foolish visitor who was up to rob her. Or if Materials can be used as source of will, she could have other plans untimately bad for our primary client wellbeing.

On the short term, this is irrelevant, we will simply have to bank on the fact that her hatred of those who robed her of her territories and status and percieved benefits of what she'd have to gain by a connection with us outweight the percieved benefit of betrayal while keeping an eye on her.

For now, a token only seems to allow for extra membranous comunication. There is no indication as of yet it allows the owner to get any uses of it we would not allow.