When i speedrun a pokemon, can i save and go back to that save? And then use an outside timer as my timing? or is this not allowed?

When i speedrun a pokemon, can i save and go back to that save? And then use an outside timer as my timing? or is this not allowed?

I saw a complete speedrun of pokemon fire red by MEvRNG and he got the wr 2:01 but i saw in the video that the timer got to 2:09 so, has werster have the actual wr? Could a moderator look in to this pls? Werster is a great runner he deserves to have the wr