What should one who enters the mosque and finds the Imam praying the funeral prayer do if he did not catch the congregational prayer: offer the prescribed prayer or the funeral prayer?

If a Muslim enters a mosque and finds a congregation praying over a funeral after the regular congregational prayer has ended, it is preferable for him to pray over the funeral with them so as not to miss it, and then perform the obligatory prayer afterwards, unless he fears that the time for the obligatory prayer will expire. Ibn Qudamah mentioned that one should begin with the prayer whose time is feared to expire. Ibn Baz stated that the funeral prayer can be missed, whereas the time for the Dhuhr prayer is ample.