The cameras will only pick up his lips, and if Suarez is talking in a thick Uruguayan accent it will be difficult to prove exactly what he said from lipreading
If the mics haven't picked up the sound clearly then you'll never prove it one way or another
The officials were all at least 30 yards away and so can't be expected to have heard exactly what was said
The players can't be trusted - no matter what the facts are the Utd players won't shop Evra and the Liverpool players won't shop Suarez. Even if a Liverpool player overheard the remark do you really think they would sell their teammate out? Likewise if a Utd player heard everything and there was no racism.
I still can't see anyone getting sued no matter what. Evra didn't get sued when he accused Bethnall in 2008, and Busquets didn't get sued for accusing Marcelo last season. Besides which, if Suarez did sue and was successful, it would open the floodgates for anyone who accused a fellow professional of diving, cheating, simulating etc etc etc. I can't see the courts being too willing to open a floodgate like that, particularly cos Suarez won't suffer any damage to his reputation if the FA exonerates him. In fact, I don't think you can be found civilly liable for accusing someone of a criminal act (or any act for which they can be exonerated by a court or disciplinary process).
In fairness if he was saying it in a thick Uruguyan accent I'm not sure Evra would have understood it anyway

If Evra is CERTAIN enough to announce it to the world that Suarez said it TEN times I find it hard to believe it won't have been picked up at least once.
On the subject of the man who tried to sue and failed you may well be right about keeping the floodgates closed but I think part of the difference here is that Evra has announced this to the world as fact without yet providing evidence and I presume before alerting the proper authorities to it added to the fact that he's made similar unproven allegations before. I'm pretty sure unless proven then Suarez would have a fair case for defamation of character.
I'm off to listen to some "Afro Carribean Sabbath" now

