It's my suspicion something happened to Madalina either the evening of the 21st of November after she was seen on video on the school bus that day or the morning of the 22nd of Nov as she did not appear at school that day. There has to be a reason Madalina did not attend school on Tuesday. So why not? She wasn't available to go. The mother has changed her story about this. First it was she last saw Madalina at noon on Tuesday when she should have been in school. I think the mother changed the timeline to coincide with the husband's departure after the argument on Wed the 23th. She alludes to a circumstance that Madalina disappeared the same time the husband did on 23 Nov. But that doesn't explain Madalina's missing school on Tuesday.
I would zero in on whatever happened Monday night that prevented the child attending school on Tuesday. Which parent was with her on Monday night/Tuesday morning. Stepdad threw Mom under the bus claiming he hadn't seen the child for a week prior to his departure on Wednesday. I think something happened on Monday night, not Wednesday night. As far as I can tell both parents were present in the home Monday night, Tuesday, and Wednesday.
Whatever happened, both parents declined to report Madalina missing, both accusing the other of "hiding" her. The fact that both parents accused the other of "hiding" Madalina leads me to believe these shenanigans occurred before, likely using Madalina as a pawn in whatever marital dysfunction. One parent (or both) played these psychological mind games before only this time one of them did something permanent. I don't know which one, but both are absolutely responsible for the lack of reporting. I think if the parents were in on this together they likely would have stuck with a joint alibi instead of directly and immediately blaming the other.
The most optimistic scenario is that one of the parents DID spirit Madalina away as a pawn in whatever psychological warfare the parents had going on. They both indicated the other parent was capable of that level of spite and idiocy. On the other hand, why would either parent sit in jail rather than reveal where they took the child, if they did? That doesn't make much sense either. If one parent knew the other had committed a terrible crime against Madalina and the other parent knew it, they would spill it rather than sit in jail.
Again, I don't think both of the parents did it else their stories and alibis would line up to cover the crime. Instead, they are pointing fingers at each other rather than sticking together with some sort of cogent story. One of them did something, I just don't know which one yet. My opinions only.