True, she had reason to resist the seizure of her phone and iPad because she knew those incriminating texts were in there, and that does show conscious awareness.Would the hospital necessarily have checked for antifreeze, those toxic eye drops, or something else along those lines?
I'm going to argue that if she did put something in his soup, you can't just blame dementia/legal insanity, because she fought with the officers when she realized they were going to access the evidence. That could show she knew it was wrong, etc. JMO.
When scammers take money from lonely/gullible people, it's a true scam and terrible crime, but if the victim then goes along with harming someone, the guilt crosses to them.
Of course she should be given a full neurological and psychological exam.
And items such as you mention which can be used as poison may not have been tested for. Is it too late now? Evidence determining poisoning is necessary to proceed with prosecution, I would assume.
Because as stated earlier she may have been only playing along for the entertainment of the internet guy. Or can say she was.