Appended Scene’s objects not casting shadows from master scene’s light?

Hi,
I’m wondering if this is a known issue.
I have a master scene that loads up initially with a ‘sun’ light and light probes.

In the app there is the option to ‘load’ (append scene) different objects.

when you do this, your loaded objects from the appended scene should interact and cause shadows via the master scene’s ‘sun’ light and interaction with light probes when they’re updated correct??

This is not the result i’m getting.
oddly only one object is causing shadows under certain circumstances that I can’t locate.

My question is, are there any specific tips or tricks to ENSURE that I get shadows cast from and on the appended scene’s objects??
( yes i have ‘recieve shadow’ marked on all objects ).

OR, the question could be WHAT would cause shadows to stop working in general.

Thanks and happy easter!