Musk says a lot of things. He is really amazing at getting press attention for himself. Ask Buffalo how Musk promises regarding the solar roof factory have gone so far...
Per your own link, Tesla has not yet satisfied the requirement. Tesla needs to hire 500 workers by April 2019, and so far has only hired 400. The other 400 were hired by Panasonic and don't get counted towards Tesla's total. Based on the abysmal/lack of solarroof sales in the past year, it's unlikely they'll need 100 new workers in the next 5 months.
Or how many Solar Roofs have been sold. I think 3 years in, they're still in the single digits.