Th0wback, when 50,000 people are using the exact same script (no matter how random it is) it is pretty easy for Jagex to figure out they are botting. I am sure that Jagex has some algorithm for looking at the how similar botting patterns are to each other. For example they could they could test a pattern and if it is above a 60% match (this is just an example) they punish the account. As a matter of fact, it is very likely they could probably tell you the exact script that you are using.
This is not to say they these scripts will be detected very often. This is simply because Jagex detection system is server-side and not client side, meaning it is not very efficient.
That simply doesn't make any sense. There are literally an infinite number of possibilities. There are 28 inventory spaces, theoretically if these were dropped randomly there are 304,888,344,611,713,860,501,504,000,000 (28!) ways they can be dropped. That doesn't take into account the factor of infinite time.