It's simple she thought Jaina was a dumb ass that would've panicked and not know what to do...little did she know she was masterminding the downfall of her and her son.
But she knows Jaina was smart enough to use Angela to ensnare Raven and put Dane on the throne and she also knows Jaina has schemed against her many times she definitely knows Jay isn’t stupid and is a danger to her and her son at this point which is why she’s trying to get rid of her with this half-baked plot I think that the queen was actually the one panicking here and didn’t truly think things all the way through and just wanted to get rid of Jay as fast as she could
Well, stupid ppl always think their smarter than what they truly are. So she thought that there would be nothing Jaina could do if she poisoned herself in her house everyone would believe that Janine did it and that would be the end...because stupid ppl don't know that they are stupid
Well that's the exact point of her plan. Since it's just the two of them, Jayna will have no other option but to call for help. The queen purposely left her servants outside so Jayna can't escape the room. But alas she never know that Jayna brought healing potion with her.
You know, it would’ve made more sense if she brought her attendant in the room with her so she would have someone to scream for help when she suddenly coughed up blood from supposedly being poison just having her and Jaina alone in the room was kinda dumb especially when the poison leaves you paralyzed