It's exactly what I was thinking, many cases have been decided based on the testimony of someone's word against another and who the jury believes. Denying the jurors in this instance of hearing the college friend in person could ultimately backfire on the prosecution even though many at this point think it helped them.
Yes, it reminds me of something I saw about that Dowaliby case. That was a case in which a little girl disappeared out of her own home. The only persons in the home had been her sibling(s) (very young children) and her two parents.
Later her body was found.
The Dowaliby thing had some things in common with this case: although there was no "smoking gun", a person was left thinking, if it wasn't the only two adults in the house who did it, then who the heck COULD have done it--aliens? I mean, there was no one else with the motive (however twisted), means, and opportunity, all coming together at the time the little girl was murdered.
Well, the police put together whatever they could. There just wasn't a bit of evidence found against the mother, but there was a slight bit, regarding the father. Not much, though.
The jury came back saying the father was guilty.
The jury was asked, and they said they had believed the small amount of evidence the state had put on against the father, and in addition the jury surprised everyone by saying they had noticed something in pics of the house--something that no lawyer had pointed out, that no one else had even mentioned. It was: that the bedroom doors in the home had big dents in them, as though someone had at some point pounded on them, while someone else would have been in the bedroom(s) with the door locked. This, the jury said, made them think that Mr. Dowaliby was more violent than he showed in public--and therefore that he may well have had a hidden, violent, side.
Now WHO would've thought the jury would have read all that into the holes on the doors?? It turned out that supposedly the holes on the doors had been there before the Dowalibys even lived in the house. (Supposedly!) But, see, the jury CAN'T ASK THE LAWYERS TO CLEAR THINGS UP! The lawyers just have to try to anticipate what they are going to really want to know.
The man's conviction was overturned on appeal--insufficient evidence.
It was a lot like this case for me. I felt one of the parents was culpable, but whoever had done it had really, really covered their tracks well.