Yes, of course they could. Then Satoshi is an intelligence agency, so Satishi is definitely exists.
Did you ever been curious about how opensource software created? Single persons, hackers collectives, agencies and corporations write something and sometimes for whatever reason publish code under some nickname. In any case they are exist.
Could an intelligence agency wrote the code?
Yes, of course they could. Then Satoshi is an intelligence agency, so Satishi is definitely exists.
Did you ever been curious about how opensource software created? Single persons, hackers collectives, agencies and corporations write something and sometimes for whatever reason publish code under some nickname. In any case they are exist.