I had the same problem. The dishwasher would run, and at the end of the cycle there was water still inside the machine. I'm not an appliance expert, but I just went through some troubleshooting. You said you disconnected the hose from the sink to the bucket on the dishwasher. I did the same thing and took a video of doing it because apparently its a common problem. I think in your case, the hose isn't clogged between the sink and machine, but rather after the sink. If you have a food disposer, or even in the absence of it, I often found that accumulation of the machines byproducts became adherent after the hose-sink junction. I disconnected all of them, and it was clear that one part in the networking of the hoses was more prone to byproduct accumulation and clogging. The clog was white in color and tough. This stuff builds up over time, almost like someone's artery, and once clogged, your best bet is to throw it out, and get a new hose. Its a cheap solution, and is usually the cause. 30,000 ppl watched my video on dishwasher repair, and a lot of them reported the same issue and solution. My "how to" video on dishwasher repair may help. I used someone else's video when I approached this issue, and the videos helped... Here it is. Goodluck!:

https://www.youtube.com/watch?v=u7uaA2NZKl0

I do have a question, forget the arm in the bottom, because that's unlikely. Believe it or not, its not usually food clogging it up, but rather the soaps. You can see in the video I attached where the blockage usually occurs.