Its just a crash, no specific error, just "heap corruption detected". However, I probably should have posted this in the Kotlin SDK community, since for Swift I am using the PopupView from the toolkit, so its just passing the popup to PopupView. Though I imagine its still the evaluateExpressions function internal to the toolkit that is causing the crash.
Here is one of the Arcade expressions that causes the crash.
var url = 'https://services.wakegov.com/realestate/photos/mvideo/'
var condos = FeatureSetByRelationshipName($feature, 'PROPERTY_CONDO', ['*'], false)
var photos = FeatureSetByRelationshipName(First(condos), 'CONDO_PHOTOS')
var photo = First(Filter(photos, 'PRIMARYIMAGE = 1'))
if (photo != null) {
return Concatenate([url,photo.IMAGEDIR, '/', photo.IMAGENAME])
}