i've done 3-days on my own before, and haven't had a problem getting helpers on the day, after checking time clashes and asking nicely. ask Janet if you can put a request up in the Stable Manager's office for a bit of help before dr, just before xc and in sj warm-up.
or, ask one of the big boys or girls if you could please borrow one of their grooms for 10mins!
I'm there and k9h is coming to help me, so I'm sure we can be around whenever you need a hand. I'm 306 so guessing my dressage will be early Thursday. Are you * or **?