As far as I know, there was no orphanage in Dustin, OK, which is in Hughes County. The largest place in the county is Holdenville, but I know of no orphanage there.
Ancestry.com has a message board for Hughes County :http://boards.ancestry.com/mbexec?htx=board&r=an&p=l...
If you cannot find someone there to look up the 1920 census, try the general board for Oklahoma. To find a board, enter the name of the state or county or surname in the search window at the bottom of every board in Ancestry.com.
The 1999 edition of The National Directory of Children, Youth & Family Services lists what appears to be the Hughes County branch office of a state agency : Dept. of Human Services, 409 Kingsberry, Holdenville OK 74848; phone 405-379-7231.
Also listed is the Juvenile Services Unit of 22nd District Court, POB 32, Holdenville OK 74848; phone 405-379-6626.
If you have access to a large library, take a look at this directory :
UNITED STATES. Bureau of the Census. Children under Institutional Care, 1923.