Informally? Perhaps. But Disney would need a formal date to take any further action after they got bit in July, so an informal date would be useless to them. I've been eagerly awaiting news that my friends in Attractions had been called back, but so far none of them have and I doubt they will until a solid date is agreed upon. It's not really up to Newsom either to just pick an arbitrary date, as it will be dependent on the data and numbers coming back on virus transmission. Any date will always be contingent on the virus numbers being at a reasonable safe level. Newsom's office can advise when they will allow a reopening, but it will always be a risk that the numbers won't pan out, or will force another closure at another point in time. Disney will have to accept some risk in deciding to reopen.
A lot of the work you are seeing completed right now, was work that was to be completed in June and July, that was intended to be done before opening. Since they stopped calling back CMs when word came down that they would not get approval to reopen, those work items have been worked on by a smaller crew over a longer period of time. While they have continued to get things ready for reopening, the majority of the work (which they pegged at six weeks initially) can't be completed until CMs return to property.
I think we have seen a ramp up of work being done in the past 1-2 weeks though, both at DLR and USH. It could be nothing, but it could also be them preparing in advance for an announcement they know is coming.
I also wonder what work you think can't be done "until CMs return to property" as they already have CMs on property just a much leaner team than normal.
Even if the CMs could get the park ready to open within 2 weeks, they will still need time to implement the reservation system, and ensure that hotel guests and guests purchasing tickets have the time required to property plan for and book a vacation.
The reservation system was already a thing with FlexPass. They will either just be expanding that system out to cover all passholders, or using the one that WDW in Florida has been using for 2+ months now. As for vacations, DLR is much more a locals park. They won't "wait for people to plan a vacation" when WDW has proven that not nearly as many people want to go on vacation right now.