Yes there's no public conspiratorial evidence in the attacks, and probably even if there was nobody wants this to escalate it into a full blown war.
Your point that Hamas is independent is challenging because there are clear links and both economic and material support comes from the Republic. That said, AFAIK (and I know very little) I've been told that their collaboration isn't hierarchical, so if Hamas decides to go in a blaze of glory, it could have been their own choice.
That said, while running the Syrian campaign Hamas had ties to other organization e.g. here, it seems that as the group shrank, their support base concentrated in Tehran (e.g. 1, 2).
What I refer mostly is this, while we can doubt the conclusions, the implications of Hamas being invited to Moscow, Bogdanov "unwavering support" and the common presence of certain materials made me think that even if neither Iran nor Russia had anything to do with it, they still had enough clarity given the support before the whole thing blew out.