So in vanilla Destiny there was a glitch and one of the bots didn't have a broom and haunted the tower after they removed the bot completely. Is this true? No. Did you fall for click bait? Yes. But I'm 90% sure that Cayde and Holliday decided to be some trolls and since they can no longer steal Eris' ship, they took the bot's broom. Amanda decided to start on a project (tricking out the broom so it can be flown like a sparrow) but later gave up and left it with the rest of her storage in the lounge room. Because it's only an unfinished product it lasts 2 weeks lol. Sorry for wasting a minute of your life