The deal comes after Disney agreed to provide free COVID-19 testing for employees, which had been a sticking point for some Disneyland unions.
SeaWorld security guards voted 23-10 against joining the same union that represents guards at Disney World.
In Disney World, the latest layoffs will affect only part-time employees after union negotiations.
The testing center will open Friday at Disney’s Maingate office complex in Kissimmee.
Disneyland unions want a plan for regularly testing employees for COVID-19 before reopening the resort's two theme parks.
Disneyland's home of Orange County, California has seen an increased number of COVID-19 hospitalizations since Memorial Day.
Segments of Disney’s vast theme park workforce are opposed to reopening Disney World and Disneyland — though to varying degrees on each coast.
Portions of Disney World’s unionized workforce are being told to prepare to return to work, according to social media posts from union leaders.