Unfortunately, for myriad factors, most of which are derived from a lack of transparency and the fact that the fox is in charge of the hen house, we will have to live in a state of Schrödinger’s Vote Tampering ->
All government officials have reasons to claim that no fraud occurred – be it self-serving or merely not wanting to be the person who opens the Pandora’s box of violence that such an admission would open (and probably coupled with the fact that no one can actually count on congressional Republicans to actually do their duty; they would much rather just blame all the violence on a lying democrat who wanted to derail Trump and is only making partisan bla bla bla).
And, to be fair, without some sort of leaked documentation/evidence, there’s also a chance that someone claiming that they’ve seen proof that there was (and that they’re in a position of authority/legitimacy with regards to the issue - as opposed to say, me, who is willing to entertain the thought that there was - but only from inference, not from proof) could just be opportunistic or attention seeking.
So, while I personally feel like, if Putin’s Kremlin managed to get as far as they did – it’s foolish to automatically consider that lack of (publicly available) evidence is completely exculpatory. No one put out a red alert regarding the possibility, even though they knew it was happening; more over, much of what we know seems to be coming from forensics/post-election discovery … so why would Putin’s Kremlin decide, “Hey, yeah, we won’t take that final step” ? – I can’t claim to have hard evidence.
That said, I think there’s enough legitimate doubt that we should redo the election. Trump’s actions merely further affirm that stance, imo.
(Sorry if this is confusing, I suddenly realized while writing that penultimate paragraph that it’s not really fair to attribute the attacks to Russia as a whole so much as Putin & his regime @ the Kremlin.)