Any of the last 3 would stop him, Gill gives him problems, but not like those 3 would...
Demitri would be impervious to the Shun Goku Satsu... and since Dimitri's power and skill is several orders of magnitude greater than that of any SFer... I say he stops at 8.
However if he somehow pulls a victory over ol'e Maximof, Orochi's divinity allows him near immunity to Akuma's offense, plus Orochi's imortality renders the Shun Goku Satsu even more useless than it would be against Gill (Even though Gill isn't actually immortal 😛 )
And last but not least, if Aku can pull out two flukes in a row, he gets splattered by Jedah... Jedahs power is of an order of magnitude not seen by ANY SFer, Bison would cream his pants if he knew this level of power existed... No way is Akuma pulling off three fluke victories in a row.