Interesting question no doubt.
I'll say No.
Only heroes can search, so if they don't do it, How can they find ANYTHING, not to mention wydstone?
The rules say "Add to the shards FOUND". In this case you found nothing, and actually didn't searched for anything.
But in the end, it's up to your group, but imo if they gain a shard even without heroes, it makes the dwarf band unfair to play against.
Hope that helps.