Filter Failure when filtering unmanaged object into Set

MongoDB Atlas App Services & Realm Realm
1

EDIT: After posting the below and opening a git report, the issue seemed to resolve itself and is not currently duplicatable

I am probably overlooking something simple but we are not able to filter an unmanaged List of objects by a managed object property, like _id on a class stored in a property and then cast it to a Set. We get this error

[General] This method may only be called on RLMArray instances retrieved from an RLMRealm

What we are trying to do is get create a group of unique id’s out of a number of possible duplicate _ids. Let me set this up

We have Dogs stored in Realm (managed) and we’ll call them d0, d1, d2…

class DogClass() {
   @objc dynamic var _id = ObjectId.generate()
   @objc dynamic var name = ""
}

And then a few People created in memory (unmanaged)

class PersonClass: Object {
    @objc dynamic var _id = ObjectId.generate()
    @objc dynamic var name = ""
    @objc dynamic myDog: DogClass!
}

Each person has one dog, but in our master list, people maybe duplicated but we want to identify dups by the dog._id that each person owns, not by the persons id. (e.g. we’re looking for duplicate dog ids)

let p0 = PersonClass()
p0.name = "Jay"
p0.myDog = d0

Then we add the people to a List

let peopleList = List<PersonClass>()
peopleList.append(objectsIn: [p0, p1, p2, p3, p4, p5, p6, p7])

I am not concerned about live objects in this example, so we create an array of dog id’s that people own

let dogIdArray = personList.map { $0.myDog._id }

Then we print them out - all works as expected

dogIdArray.forEach { print($0) }

outputs

60258749aefaa155e1c31265 (dup)
60258749aefaa155e1c31266
60258749aefaa155e1c31265 (dup)
60258749aefaa155e1c31266
60258749aefaa155e1c31265 (dup)
60258749aefaa155e1c31265 (dup)
60258749aefaa155e1c31267
60258749aefaa155e1c31265 (dup)

but then here’s the trouble

let uniqueIdArray = Set(dogIdArray)

crashes with

[General] This method may only be called on RLMArray instances retrieved from an RLMRealm

and one other thing, even if we try to get a specific owner via it’s dogs id, the same error occurs.

let jayOwner = peopleList.filter("myDog._id == %@", d0._id)