Hi Friends!
We’ve started using Journeys some months ago, and as we’ve matured our use cases we’ve started experimenting with customer experiences.
Would love some advice on how to chain journeys together. We have a use case to experiment the customer experience during a feature onboarding flow. We’d like to experiment with application onboarding experience, messaging, and in-app messaging.
To do this, we need to split our audience into 3 branches. 
Each branch then moves the customer into a journey. (3 journeys) 

What i’m trying to do is create an “allocation” journey that branches the audience into 3 “random” branches. I’ve created a couple of test journeys to illustrate this.

Then a “stream” journey that defines one experience.
 

I was able to do this by defining the entry condition step to mean that a customer 
 

The issue i’m having is that the numbers of customers starting in the stream journey is erratic.  Example we have 43k users in each branch in the “allocation” journey but only 227 seem to have made it to the “stream” journey.
I also find it quite difficult to triage what is going wrong as, there’s not really a debugger view to help uncover data issues. I’ve used webhooks with no URL as a way to be able to bucket customers to help with this, but it’s not ideal.

The other option i’ve explored is putting it all in one giant journey, but this can get quite unwieldy and is difficult to make changes without affecting customer experiences in other branches.

Any advice would be greatly appreciated.