In my opinion I don't think that Disney can open select DVC resorts without opening them all. Especially since DVC dues pays for the operating costs of DVC's portion of the resort. I have not really thought about the excuse of Disney cannot afford to open say the BCV because they cannot afford their share of the shared expenses. Things like transportation, grounds keeping, shared area cleaning, security, etc. I don't know how far the shared expenses are at BLT go. I don't know that much about BRV do they share the lobby with Wilderness Lodge? I would guess if they do then the same would apply to them as with BCV, Poly, etc.
I do think that if Disney opens say the Grand Floridian they then have to open VGF, SSR, OKW, RIV, and Kidani.
I feel like WDW will be open in Aug. And after thinking about what Sandisw wrote I think that Disney will open the DVC resorts regardless of if they open the parks at the same time. The only thing that DVC owners are guaranteed is the room not the parks, restaurants, and shops.