This is all true, but the Resolutions of Charter are quite clear that in using the term, "member of the covenant," and "members of the council." Neither of these apply to employees and agents of the covenant (those should be in the charter, but that's not how it is written, hence the loophole.
In fact, having just reread the Resolutions and Charter, “Members of the Covenant” as defined in the Charter ONLY applies to Journeymen, Masters and Pontifex (ranks and membership section). There are three “classes” listed; Members (as described above), Guests (which included Protected Guests, Honored Guests and Past Masters), and Covenfolk which it explicitly states employees fall under. Thus employees are clearly NOT “members”. And in that case Selim could in theory make a claim (though he won’t since he was worthless and feels ashamed about that).
As I said, that's where Vibria's telling of the events will sway things.
The Charter states, "The covenant also lays claim to other shares of properties and portions chattels in the village of Arans and in scattered locations nearby. These including the silver mine, the orchard, and the vineyard."
So while it’s true that the incident took place on covenant land, a dragon's scales are not property (clearly meaning real property based on context) or chattel (the scales are not "movable personal property" owned by anyone), nor do they fall under the given examples of "the silver mine, the orchard, and the vineyard."
That's why I quoted the two sections on "unclaimed and undisputed sources of vis, mystical resources, and other assets," and "all magical items obtained by members of the council while acting at the behest of the council,” as they are more relevant to the situation. And as I stated, each of those provisions only cover “members of the covenant,” and “members of the council.”