Creation of Maya Sita
Lord Shiva said—'Oh Parvati! Here, becoming aware of all the conspiracies of Ravana, Sri Ram advised Sita when they were alone, 'Oh Sita! Listen to what I have to tell you. Oh the auspicious one! Ravana will come to you disguised as a mendicant. Hence, by my orders, you must enter the holy fire leaving behind your lookalike shadow in this hut, and stay there in the fire in an invisible form for one year. After that, after the killing of Ravana, you shall get back to me once again.’
Hearing these words of Sri Ram, Sita did as she was told. She became invisible in fire, leaving behind a shadowy Sita.
- Canto 7, Aranya Kanda, Adhyatma Ramayana.
It was this Maya Sita whom Ravana kidnapped.
After Ravana was killed, it was Maya Sita who did Agni pravesha, not real Sita. When Maya Sita entered the fire, she disappeared and the real Sita was brought out by Agni Deva
‘Oh Hari (Sri Ram)! You had created an illusionary/shadowy Sita for the express purpose of destroying (i.e., killing) Ravana along with his sons, kiths and kins and comrades etc. Oh Lord! By doing so, you have removed the burden of this earth.The illusionary/shadowy Sita who was like an image of her real self has vanished after having accomplished the task for which she was created.’ Hearing these words of the fire God, Sri Ram worshipped and honoured him with great delight and a joyful heart and then he gladly accepted Janki (Sita) who was most happy and cheerful (at this happy turn of events).
- Canto 13, Lanka kanda, Adhyatma Ramayana.
So Lord Rama never questioned Sita’s character in Adhyatma Ramayana. The fire ordeal was merely a way to switch back Maya Sita with the real Sita.