Unitary Event Condition Not Triggering Journey Entry Despite Matching Profile Event Data

I'm trying to trigger a Journey entry using a unitary event condition based on an unsubscribe event coming from a landing page.

Entry condition used:

(isNotEmpty(@event{All_Consent_Update_Event._experience.customerJourneyManagement.messageInteraction.subscription.subscriptionListID})) 
and 
(in(@event{All_Consent_Update_Event._experience.customerJourneyManagement.messageInteraction.subscription.subscriptionChoice}, ["no"]))

Context:

• When a profile unsubscribes via a landing page, the event is correctly generated and visible on the profile.
• Under messageInteraction.subscription, both subscriptionListID and subscriptionChoice are populated with the expected values (subscriptionChoice = "no").
• However, when this same event/condition is used as the entry trigger for a Live Journey, the profile does not enter the journey.

What I've already verified:

• The event is present on the profile timeline with the correct field values.
• The XDM path used in the condition matches the schema field path on the event.

Questions:

1. What could cause a Journey not to trigger even though the unitary event condition appears to match the event data on the profile?
2. Are there known restrictions or limitations when building unitary conditions on nested fields (like messageInteraction.subscription) within OOTB XDM schemas (e.g., array-type or object-type fields not being fully supported in entry conditions)?
3. Are there best practices for constructing unitary conditions against nested/array subscription objects to ensure reliable Journey triggering?

Any insights on schema field indexing, event dataset configuration, or condition evaluation timing that might explain this mismatch would be greatly appreciated.