No I haven't yet, but I have go the quest to be done, so the first stage of "investigate this". It could be something to do with that. Would be an interesting back-story to the Deathclaw
Go do the quest, its a good one, and relevant to your post.
I've done the quest on a different run through, so I can try.
Of course though, the Deathclaw would likely despawn due to me moving away.
The Deathclaw found on the road strikes me as a random encounter. It being non-hostile may or may not be intended. It probably will go poof after you leave if you stay away long enough.
The one you find at the end of Devil's Due will sit there forever.