Bro. Nowadays the mainstream media has been proven lying so often and so hard that it is 90% of the time safer and truer to always conclude the opposite of what the media provides! I'm sure you already experienced that.

So yeah, I'm not actually going off from nothing I'm going off precisely from the said media and with a bit of scepticism on the Iranian version of the story. They wanted to lie about the modus operandi citing cyber attack from Israel to make the story big and striking but it doesn't add up bro. This is their second hall they built in a short amount of time after the first one was destroyed (by sabotage allegedly by Israel) this new hall has been rushed with little consideration to safety measures, i.e. incompetence.

We are largely speculating as we are not in situ but honestly, not this time. the Mossad can do it, does it very often actually, but nah, not this time. The story was reported waaaay differently than when the Mossad usually does it.