Most nuclear incidents do not involve stuff blowing up, but rather stuff leaking. As for covering things up, that's a specialty of this field, as any former nuclear insider will tell you.
We do not know the same "insiders in the field" then.
As a former electrical engineer, many of my friends works for EDF in Nuclear. And none of them ever talk about covering things up.
It is quite the opposite, any minor incident generally trigger a ton of process and often a partial shutdown "just in case".
Every possible interaction with the installation is documented, planned and part of a process with X layers of human verification before any intervention.
I do not know how the nuclear industry run in other countries but that is not the culture for EDF to cover things up. For politicians with their own agenda, it's an other story....
2008: Greens/EFA report says official "energy independance" stat of 50% of a lie; when calculated on final energy not primal energy, it falls down to 24%, and down to just 8.5% when you take into account that uranium is in fact imported; it also touches on engineering issues, staffing problems...
2011: As part of a Greenpeace report about EPR, two insiders reveal serious defects https://www.sortirdunucleaire.org/IMG/pdf/greenpeace-2011-05...
2013: The post-Fukushima audit revealed no french setup takes such scenarios (no water/electricity) into account. https://www.sortirdunucleaire.org/IMG/pdf/globalchance-lapon...
2017: EDF/Areva knew since 2005 that they relied on an unreliable factory for building sensitive equipment https://www.franceculture.fr/economie/scandale-de-la-forge-d...
2021: A whistleblower denounces defects he's been silenced about, says he's a nuclear lover but torn apart by this worrisome situation and sues EDF for endangering people's lives https://www.francetvinfo.fr/societe/nucleaire/centrale-nucle...
And there's of course the many many many incidents we barely hear about, when at all: https://www.sortirdunucleaire.org/Nucleaire-des-accidents-pa...
If it can reassure you, i'm also very skeptical of greens and greenpeace because they've been corrupted/coopted by big business over the years and don't stand for actual ecology (degrowth/anticapitalism) anymore. Such reports is one of the few instances of them still doing a good job on specific issues, so i thought taking these serious sources instead of more radical material would take us closer to an understanding.
There are no reports for leaks I could find, so while you can point at other bad actors in the field, why don't you celebrate the little wins of some company being transparent enough for once?