Redmond is eliminating the course at Juel Park but has promised to put one in somewhere else. Perhaps Marymoor is one of the possibilties; at any rate, it sounds like the city will probably be paying for it out of their parks budget.
More info about the demise of Juel here:
http://www.odsa.com/forum/viewtopic.php?t=9500
I don't know Marymoor Park, but from what I can see about it on-line, the main part of the park is probably too heavily used for a disc golf course. From
aerial photos, the area near the lake shore
might be promising, but it also looks suspiciously like it might be a very big swamp.