You’re somehow right, this’ll happen 5 times out of 6.
But the corp can still purge while Turtle is the only breaker, and the situation stays the same.
Now, odds to draw 1 seeker out of 3, then 1 out of 2, then 1 out of 1, and not drawing agendas out of X is never considered a question by people who don’t play the corp…
If I remember well my stats, drawing 3/3 in a 45 runner card happenned half of the time when there was 18 cards left in stack (would have to recount that). In your 44 cards long deck, there is consequences to consider about your agendas drawn there.