Is there any reason you can't book this on united.com? You'll save yourself the booking fee. You will need to play around a bit with the multi cities option.

I am not sure why you find this to be a good deal. You aren't getting tons of extra miles for the extra cost of paying a booking fee (if you go that route). You could get more miles heading to SFO or LAX first and then to DUB with a simpler routing. It also seems strange that you are using an international itinerary to accumulate segments. It would be much wiser to go for miles.