Answer
Wrap the OR'd Objstate conditions in their own parentheses within the $filter expression — for example, (Objstate eq IfsApp.CustomerOrderHandling.CustomerOrderState'Released' or Objstate eq IfsApp.CustomerOrderHandling.CustomerOrderState'PartiallyDelivered') — rather than combining them loosely alongside other filter conditions. Proper parenthesization of the OR'd values, matched against the correct enum-type naming, is what makes a multi-value Objstate filter actually work in a Lobby navigation link.