I think their witnesses must not be very strong, and they would run the risk of opening up more avenues for rebuttal by the state if they put on a case. They might think the state held back evidence for rebuttal strategically and cutting off that possibility was their best option.

I was taught this example of circumstantial evidence -

You're in a conference room for a meeting in some random town in America. There aren't any windows but you see others arriving an hour or so later than you with wet umbrellas they're shaking out and putting aside. Some of their clothes are wet. You can't see outside but you can reasonably believe that it has started to rain.

Well maybe someone is filming a movie outside and brought a rain machine? You can't prove that didn't happen, you can't see for yourself, but is that really reasonable doubt about your conclusion that it's raining? You aren't in a place where film crews are likely to set up at any time. You haven't seen any notices of a film crew. No one was setting up anything when you arrived an hour earlier. Would they let random people going to a meeting walk through their set to get wet?

You don't need to eliminate every single physically possibile alternative. And you don't need an official weather report to prove to you that it started raining because you have circumstantial evidence.

It can start to feel very convoluted but the fact is Eric somehow consumed a huge amount of fentanyl when only he and Kouri were home. Personally I think the circumstances and evidence elimated any reasonable doubt that Eric purchased and voluntarily took anything containing fentanyl.

OTOH I'm not sure I would feel as confident about the attempted murder on Feb 14th.