RAD but highly attached?

Yes, it is possible.Look up the DSM criteria for diagnosis.RAD isn't just a failure to attach. It's a persistent, developmentally inappropriate attachment response, which can also include acting overly familiar towards strangers. And, it doesn't necessarily happen in all situations, but the attachment response happens in most situations.

If there is an attachment, it can not be a healthy attachment. It could be a trauma attachment. Or a very insecure attachment. Or they could be non-attached foster parents who run (essentially) a boarding house. (That's not bad, by the way, some kids do best in that setting.) Or, it might not be any kind of attachment that the child is showing to the foster parents. It might be really good faking. Or the worker could have been fooled by surface stuff - remember RAD kids are not going to show to strangers what they show in the house, so what the worker saw could be in the child's profile rather than what the foster parents report. Or the diagnosis could be wrong. Some people hear "attachment issues" and immediately jump to RAD. Some attachment issues on the milder side of the spectrum can co-exist with strong attachment to a caregiver. And of course there is the possibility the RAD diagnosis is old. If it is quite a few years old it may have been healed since then, depending on the age of the child. Could be a number of things, obviously. But it is not a healthy parent-child relationship and a current diagnosis of RAD.

Thanks for the feedback so far. Diagnosis was several years ago but it's still listed under his current issues. Child participates willingly in attachment therapy and experienced foster parent reports an appropriate bond.

It's great that you are questioning the diagnosis.Many believe that adoptees and foster children are overdiagnosed and misdiagnosed with RAD.

Sometimes its difficult to determine the gravity of the attachment issues until they are with their "forever home" My daughter def was a little dazzler in her foster care setting because she was surrounded by kiddos in the same circumstances. She was fond of her foster mom but I question a true attachment. Once she moved in we have had to work really hard with a therapist because she was convinced it was a temp situation- once she realized it WASNT thats when I realized that she had issues with attachment.