I'm not sure if I fully agree with that. But this is mainly based that in my country (NL) theaters have restarted. Granted most are small intimate shows (Stand up comedy, small bands), big musical shows are still out, but one has restarted already and another show will follow soon. Audiences are limited and the first show has made some changes in their staging. I haven't heard anything yet about shows being cancelled due to infections of cast/crew.
I am more wondering if
Disneyland Paris was careful in their training facilities, how/if the cast members got tested. For Jungle Book Jive the performance space was going to be huge and outdoors. There is plenty of space on stage for the cast to stay at least 6 ft away from each other. Except for one singer at the end, the majority of the show has pre-recorded singers. Maybe there wasn't a lot of space backstage for the cast to socially distance. Poor ventilation in the training facilities, maybe.
Other question is: Could Disneyland Paris ask their cast members to isolate themselves while they were in this show? I mean, when the cast went home after a day of work, they should stay at home, not go out unless necessary. Maybe DLP has asked this, but in reality that was undoable.