You still didn't answer vasquo's question, and i'm having a hard time understandig your question and your goal.
Your schematic is also hard to read and what i can read doesn't make any sense to me (but ofcoure that can be me).
But am i right to see you are trying to replace the button by the 2n2222 ?
The button has 3 contacts, P1, P2 and P3 and your transistor is across P2 and P3.
The button connects P1, P2 and P3 all together (strange, but that's the way it is drawn).
And you just connect P2 and P3 with your transistor.
P1 is tied to the 555, P2 and P3 are not.
So any interaction between your transistor and your 555 is impossible.
So there's your difference.
Do you really need to use this strange switch (why ?) or can you do this an other way ?