So just decided to watch Gokaiger vs Go-busters again and the one scene where Gai said he had a good place to safe keep the letter which J suggested writing suddenly struck me as a missing scene so I decided to write this one shot. I'm going to make something up so just go along with it for the story's sake and this is an assumption that this conversation happened AFTER the Zangyack were defeated but before the group left to fight the Zangyack on their home world Also an honorific is used at least once so some understanding of the Japanese culture is needed or at least appreciated

Youko and J were confused as to why they were at a compound

"Gai-san, why are we here?"

"You'll see"

And so Gai enters and asks to see the head of the Shiba clan which was granted

"Why do you wish to speak to me?"

"Shiba-san this is...not easy for me to do but I request that this audience be private for safety reasons"

"Why should I believe you need privacy for safety reasons? I do not know you and then there is the fact that I was told by the guards that you told them you were armed"
Due to the fact that the audience was currently public Gai was uncomfortable revealing the truth about J or revealing his secret regarding the ability to morph and the fact that they were from the future, and then remembered a conversation he had right before the group left the planet to fight the Zangyack on their own turf

A while back

Gai and the crew were relaxing and recovering from the battle that they had just fought when suddenly Shiba Kaoru showed up and requested to meet with them

"You wished to speak with us?"

"Yes, I don't know why but I have a message that needs to be given to Ikari Gai, and this message was passed down from one head of the Shiba clan to the next for 250 years"

And so Gai and Kaoru head to a private area

"Gai, if for whatever reason you need the assistance of the Shiba clan I want you to tell the leader of the clan this 'Samurai are honor bound to follow the way of the warrior, however they are also honor bound to help those that need it, the Shiba clan even more so then others due to who you are thanks to the Emperor, as someone who knows someone close to the head of the Shiba clan in a way I can't explain in public I beseech you to listen to my words and consider my request seriously' I don't know why this phrase is needed but it is"

"And the whole part about the former head of the clan?"

"Though rare there are times when the current head of the Shiba clan stands down and allows their heir to lead while they themselves are still alive"

"Then I shall remember your words and hope I never have to use them"

Present

Gai takes a breath and then calmly speaks up again

"Shiba-san, Samurai are honor bound to follow the way of the warrior, however they are also honor bound to help those that need it, the Shiba clan even more so then others due to who you are thanks to the Emperor, as someone who knows someone close to the head of the Shiba clan in a way I can't explain in public I beseech you to listen to my words and consider my request seriously. I know that this is asking a lot of you, however I'm afraid that desperate times make for desperate actions"

"I see...let us talk in private then for you speak in a way that says you know what you are talking about"

And so Gai and the head of the Shiba clan go to a private area and that's where Gai reveals that he and his companions are from 250 years from the future and gives proof of that claim

"I see, what can the Shiba clan do for you and your companions then?"

"We need to write a letter to our allies that are in the future to let them know where we are, I am asking that the Shiba clan hold onto the letter to be delivered on the exact date and time that the person writing the letter requests"

"We shall do so then, I just hope that the person who writes it does the calculations right or this could wind up being problematic for the future"

"Same, but she should be able to do so"

And so Gai returns and Youko is given a scroll to write her message on in a private area and once finished she gives it to the head of the Shiba clan without a word knowing that Gai had already spoken for her and then they leave the compound

"Now all we can do is wait and hope the group gets the message"

"Indeed"

And so J, Gai and Youko simply waited hoping that the letter would reach the Go-Buster headquarters in the right time period so that they could hopefully be rescued