Well, so much for the "there's no evidence of collusion" argument, since Donny, Jr. yesterday ADMITTED that they were trying to collude with the Russians.
His first story was that the meeting with the Russian lawyer was about international adoptions from Russia. But then, within 24 hours or so, he issued another story -- the meeting was SUPPOSED to be about evidence that Russia had been helping Hillary, which is why he set up the meeting, but the Russian lawyer didn't actually have any evidence of that, so the meeting was mostly about international adoptions from Russia, and once that became clear, the Trump contingent left. Oh, and by the way, his father didn't even know the meeting was being held in HIS building while HE was there, and neither Jared nor Manafort had any idea who they were supposed to be meeting with or what the meeting was supposed to be about.
Let me use Occam’s razor to propose another explanation: The meeting was about dirt on Hillary alright, but it was about what the Russians had learned from hacking the DNC and Podesta emails. And one of the things the Russians wanted as a pay-off was the repeal of the Magnitsky Act, which they were assured could be arranged. And sure enough, within a week after the meeting, the leaks of the hacked emails started being published.
No, there's no direct evidence of that, but the circumstantial evidence fairly screams it. Insisting that somebody who was in the meeting explain exactly what happened is like saying it's not enough, in a divorce case based on adultery, to show clearly that the spouse and a suspected lover were seen kissing passionately, then checked into a motel, spent the night there, and were then seen kissing passionately before they each got into their respective cars and drove away. Sure, it's POSSIBLE that they spent the night innocently engaging in a discussion of their mutual interest in ancient Chinese literature, but a finder of fact is perfectly justified in concluding that the explanation is a lot less innocent than that.
Donny Jr.'s explanation is about as credible as the guy who was tried for burglary back when I was clerking, whose defense for being found in somebody else's house when they came home is that he hadn't broken into their house to steal anything, he had merely done it to use the bathroom (never mind that he had burglary tools with him at the time).
Junior's explanation is what was called a "modified limited hang-out" on one of the Watergate tapes. He's admitting just as much as he's pretty sure can be proven, and even though that's pretty bad, trying to put the most innocent interpretation possible on it. That's never very believable, but it's even less so when you've repeatedly lied about the subject of your new story.