Bringing in Khidr would not be the right choice. His clarifications are not so easy to understand. Look at how difficult it was for Musa (A great Messenger of Allah) to stay in his company. The Ummah is already divided on the status of Khidr ie whether he is a Prophet or not, is he still alive or not, etc.
Secondly, how would one establish a Jinn to be from the Salaf, let alone as a Sahabi or a Tabi'i. Is a testimony of a Jinn valid for us Humans?