Tried several times and I reproduced this issue every time. Maybe is unique to Sunken Temple for some reason but it's the first time I have issues with this load condition.

After entering Sunken Temple raid in Season of Discovery the statuses using the load condition Instance name/ID doesn't work until /reload is done or condition is unchecked and checked again.

Also noticed while doing these recordings that some other statuses with load condition set to Eastern Kindgoms/Kalimdor were still loaded inside Sunken Temple until I did /reload.

Didn't test in BFD or Gnomeregan and maybe will have problems in the future if blizzard decides to change any other dungeon into a raid.

Proof here.

Proof #2 (doing normal entrance route from Swamp of Sorrows)

It seems in SoD blizzard developers forgot to fire some important events in the new raids.
Try out 2.8.32-beta-classic version.

Works fine now. Tested it in different ways and all good. Thanks!