Possible scenarios include.
1. The women overheard conversation, but misinterpreted what they were saying. (both parties innocent).
2. The men did make these comments because the women noticed them. (Men guilty - women innocent.) 3. Your scenario (women guilty - men innocent).
4. Men knew they were saying these things to upset women, but she knew they were yanking her chain and decided to call the police to teach them a lesson. (both parties guilty).
Right now, the women says she overheard the men. They say she is lying and the reportedly the son told hi mother the men were yanking her chain. Observations about who looks truthful are not helpful because our personal biases have more to to with our opinion than the facts.
Until some hard evidence appears to support one claim over the other, the most we can conclude is we don't know.
Your other scenarios all assume that the men actually said something at least similar to what Eunice claims she heard. The perps are claiming to have not said anything at all remotely like it.
So according to the men who you have been defending, none of your scenarios happened.
The most likely is either your number two, or these guys are involved somehow in terrorism but there wasn't enough evidence when they were pulled over to prove it. The least likely is that the men are telling the truth, since their statements do not ring true, for reasons repeatedly cited throughout this thread.