Kashin Koji Jippo question

Something bothered me about one of Kashin Koji's use of the Jippo : making people learn techniques they would aquire in the future.

No problem with the process but... Time wise , That's odd.

I was under the impression the future would be quite doomed by the Shinjus and that's why the emergency is to prevent that but...

When Kashin Koji "taught" Hiraishin to Boruto , he said It took six years to his future self to develop that technique.

The exact time of Boruto meeting Koji during the 3 years timeskip is unclear , but by just being logical it means that Kashin saw at least one future in which Boruto gets to live 3 years + after the start to TBV events , doesn't it ?

Soooo... did I miss something ? Is it that Kashin Koji saw a good ending but is withholding it ? Are the Shinjus really that lazy that they would not doom the planet for at least 3 more years ?

I'm a bit confused.