Ref. No. 41/1041
In the name of Allah the most gracious the most merciful
The answer to your question is as follows:
A Musafir Muqtadi behind a Muqeem Imam will complete his namaz just as a Muqeem Masbooq does. He is obliged to offer full namaz and must do Qirat (Fatiha cum Surah) in the first two rakats of the missed rakats. Qirat is not mandatory in more than two of missed rakats.
And Allah knows best
Darul Ifta
Darul Uloom Waqf Deoband