Those who were not able to continue following the imaam in Friday prayers because the electricity was cut off

Dear Brothers & Sisters,
As-Salaamu-Alaikum wa Rahmatullahi wa Barakatuh. (May Allah's Peace, Mercy and Blessings be upon all of you)
One of our brothers/sisters has asked this question:
A group of people were praying Jumu’ah in the basement of the mosque, and during the prayer the electricity was cut off and they could no longer hear the imaam. One of the worshippers stepped forward and led them in the rest of the prayer. What is the ruling on their prayer, knowing that he completed the prayer as Jumu’ah (i.e., two rak’ahs)? 
What would be the ruling if no one had stepped forward to lead them? Should each person have completed the prayer on his own? If that is permissible then should it be completed as Zuhr (four rak’ahs) or Jumu’ah (two rak’ahs), since they had listened to the khateeb and had started the prayer with the imaam and prayed one rak’ah with him?
(There may be some grammatical and spelling errors in the above statement. The forum does not change anything from questions, comments and statements received from our readers for circulation in confidentiality.)
Check below answers in case you are looking for other related questions:
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Answer:

Praise be to Allaah.

If the situation was as described by the questioner, then the prayer of all of them is valid, because whoever catches up with one rak’ah of Jumu’ah has prayed Jumu’ah, as it says in the saheeh hadeeth narrated from the Messenger of Allaah (peace and blessings of Allaah be upon him). If one of them had not stepped forward and they had each prayed the final rak’ah alone, that would have been OK, as in the case of one who joins the prayer in the second rak’ah with the imaam, then makes up the other rak’ah by himself – because of the general meaning of the hadeeth in which the Prophet (peace and blessings of Allaah be upon him) said: “Whoever catches up with one rak’ah has caught up with the prayer”. And Allaah is the Source of strength. 

Whatever written of Truth and benefit is only due to Allah's Assistance and Guidance, and whatever of error is of me. Allah Alone Knows Best and He is the Only Source of Strength.
Your brother and well wisher in Islam

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