Out of the three bots, only Bot GPT 3.5 made a mistake in its synthetic division. It incorrectly arrived at a quotient of 1 - 2x - 8 instead of the correct quotient, which is x^2 - 2x - 8.
On the other hand, Bot solved it correctly by factoring the expression x^3 - 5x^2 - 2x + 24 as (x-3)(x^2 - 2x - 8). It correctly identified x-3 as one of the linear factors. However, it seems that Bot made an error in choosing the correct zero from the given choices.
Step-by-Step Bot, unfortunately, made an error in its synthetic division and was unable to arrive at the correct quotient. Therefore, it couldn't find the correct zero.
In conclusion, Bot GPT 3.5 and Step-by-Step Bot did not provide the correct answer or methodology for finding the zero, while Bot solved it correctly but failed to choose the correct answer from the given choices.