I wouldn't discount it. In my mind that's likely why they set their opening date so far after everyone else's - to give them time to evaluate how things go, take and apply learnings, and give themselves an opportunity to hit the red button if needed.I say it again, I will not be surprised if Disney pulls the plug on reopening.
On the other hand, I suspect that's probably not desired if at all possible. At the moment things don't look like that will be necessary (for example hospitalizations don't appear to be going up drastically yet; Florida has been averaging about 30% of available hospital beds and 27% available ICU beds for the few days based on hospital reporting to Florida's Agency for Healthcare Administration here: https://bi.ahca.myflorida.com/t/ABICC/views/Public/HospitalBedsCounty )