The ruling on one who catches the imam in bowing and does not complete the dhikr

The questioner:
Honorable Shaykh, may Allah grant you success, a man.

The Shaykh:
Allah did not permit this except as an obligation.

The questioner:
A man caught up with the congregation in the second rak'ah of the Fajr prayer, so he said the takbir for the prayer. Then the imam bowed, and the man recited the opening supplication (du'a al-istiftah). Then he said the takbir for bowing, but he did not complete the supplication for bowing. Then the imam raised his head, and the man became uncertain whether that rak'ah counted for him or not. When the imam finished the prayer, he stood up and prayed two rak'ahs. Is what he did valid?

The Shaykh:
If he catches a rak'ah, and he catches the imam in a rak'ah or before the bowing and bows with him, if he catches the bowing and bows with him, the rak'ah is valid for him. If the imam says the taslim, they say he has only caught one rak'ah. And if he left saying "Subhan Rabbi al-Azim" (Glory be to my Lord, the Exalted), he prostrates. The women in the rak'ah come back with the rak'ah that was missed from him and he reveals himself from the obligatory harvest of saying "Subhan Rabbi al-Azim." Yes. He repeats the prayer, but by the ruling that he is ignorant, it is not said he repeats the prayer because of the ignorance. Yes.