Who was the Man that Rescued Ayesha?

Who was the Man that Rescued Ayesha?

Ibn al Hashimi states:

young Muslim man named Safwan (رضّى الله عنه), who had fallen behind the army after taking a rest, reached the camp during the night and found her lying fast asleep. Safwan (رضّى الله عنه) recognized her and escorted her back to the Muslim army and the Prophet (صلّى الله عليه وآله وسلّم).

Unfortunately, some hypocrites who had seen Safwan (رضّى الله عنه) and Aisha (رضّى الله عنها) arrive alone together began to gossip and spread slanderous lies about them. Eventually the story reached the Prophet (صلّى الله عليه وآله وسلّم) himself and by then the whole community was talking about what might or might not have happened between the two young Muslims.

Naturally, the believers were certain that nothing bad had happened, but the Munafiqoon (hypocrites) thought otherwise and were not afraid to insinuate that was the case, accusing the Prophet’s wife of engaging in an adulterous affair.

• Ibn al Hashimi suggests Safwan had taken a rest, what is his evidence? We see nothing from Bukhari that informs us of this. Moreover there is nothing from the tradition that suggests that the Prophet (s) had ordered Safwan to go and locate his wife. If anything he (s) would have located one of her mahram relatives. No decent man would send a non-mahram man to bring his wife back to the camp. So the question is what was he doing there? Moreover for the sake of clarification:
• Who was Safwan bin Al-Muattal As-Sulami Adh-Dhakwan? Was he from the Muhajirin, the Ansar or some other tribe?
• Why was Safwan bin Al-Muattal As-Sulami Adh-Dhakwan so far behind the departing army; did the Prophet (s) order him to remain behind or was it of his own volition?
• We see no evidence of the Prophet (s) determining whether or not Ayesha was in the tent, when she finally caught up with him, did she not seek to vent her legendary frustration and inquire why her husband had not at any point checked to see if she was there? Would a normal wife not find this lack of care unusual and indeed hurtful?