You can find the details mentioned in the following experience league documentation links https://helpx.adobe.com/legal/product-descriptions/real-time-customer-data-platform.html  https://experienceleague.adobe.com/en/docs/experience-platform/ingestion/streaming/overviewhttps://experienceleague.adob...

Can you add Journey Orchestration Service as well to your integration project ?

You will need to add this to your URL's directly within the email designer by referring to the contextual attributes. It is not available at the channel surface level

You will have to stream data into AEP matching the event criteria for the unitary event journey to trigger.

At the read segment level, the minimum profile reading rate per second is 500 where as for the custom actions, it is 200 tps. https://experienceleague.adobe.com/en/docs/journey-optimizer/using/configuration/configure-journeys/external-systems/throttling  Also, are you using the end points specified ...

Depending on your case, you can let the journey run daily and have one of the following time filtering options specified in the Conditions activity (https://experienceleague.adobe.com/en/docs/journey-optimizer/using/orchestrate-journeys/about-journey-building/condition-activity#time_condition) along...

You can refer to this recommendation https://experienceleaguecommunities.adobe.com/t5/adobe-campaign-standard/embed-video-in-an-email-in-adobe-campaign/td-p/356765 

Can you try it on the following lines and see if that works ? #{ExperiencePlatform.ProfileFieldGroup.profile._tenant.audienceEnrichment.entry('AO').audienceEnrichmentChildMap.entry('<audienceId>').tenant_nr_travels}>= 6 

From the feedback status enumeration, it has the following value and display names for duplicate. It essentially means the push message was skipped as there was already a record targeted with a similar namespace. value - display nameduplicate - Duplicate message skipped

It is recommended to go with a new subdomain.Reference - https://experienceleague.adobe.com/en/docs/journey-optimizer/using/configuration/delegate-subdomains/about-subdomain-delegation