Jay,
Idea #1:  Jeff Easter used to work at Holiday Motorhomes in Fife and later, Beaver Coach Sales.  Before that it was Tweton's.  He was the salesman that helped BJ and I.  I recently talked to him and he now works at Tacoma RV in Fife.  He may be able to tell you where the techs from Holiday Motor Homes are working.
Idea #2:  Northwest Camping Center sprung up in Fife as the other were closing down.  They have lots of what appears to be consignment inventory and every appearance of a shop.  It may be were some of the techs went from Great American RV, the Monaco dealer and Holiday.
Idea #3:  Paul Evert's has been recently mentioned as a star Navistar/Monaco dealer.  I've driven by their lot in Fife a couple of times.  There may be someone there with some knowledge of Monaco products. 
Idea #4:  When Wally Kimble and I drove our wives to Newfoundland he had about the same coach as you.  He had a the same bedroom slide malfunction.  We took it apart from the inside and found a bolt that had worked loose.  It may be as simple as that. 
Idea #5:  Blue painters masking tape will seal most anything for a few hours and peals off easily.  Drive it to Bend.
Idea #6:  Call BCS and ask them where to take it in the SeaTac area.
Good luck!