What you could do:
Use ServerEvent => MultiCastEvent to spawn your Actor. So everybody has his own one instantly
User the Server to tell the Client about the spawned Actor => Set the Reference
Check the valid status of the spawned Actor until it is valid and only then execute the ClientEvent
Can you share a project or an example? Or describe what you spawn and where? E.g. do you spawn it in your character? How does the pickup event look like etc