It is inconceivable to me to even wonder if we could shell the Zaporizha power pant. No, we do not want to repeat that tragedy and we love out country. We do not want to make it uninhabitable.
No, it is impossible that we put any military hardware near any of the nuclear plants (besides air defense systems far away from them).
It is very difficult for external observers to verify who shelled the plant, as you need specialized radars for that. Russia has them, and it would make this data public if it could prove that Ukraine did it.
The idea that Russia is using nuclear blackmail, but reframes it as “Ukrainians are doing it” is way more plausible for me.