Yup, he doesn't know the current jutsu...that's why oro said the hype in past tense, the only jutsu I would argue he could know is rasengan... and that's only because it's basic chakra control..even kakashi was able to reproduce it...Nonetheless , still conjecture..
he most likely does not know how to use ftg, etc...Though he continued learning jutsu even after his prime state had passed (shiki fujin) , we don't know to what extent he continued ..minato, since he created shikifujin , would have written it down in the forbidden techs scroll, and possibly after his death hiruzen read and learned it
That could be an example of hokages passing down techs in those scrolls..