Good that the workaround works!
To understand the original problem, have a careful read of:
In particular:
Although a workflow is created as a linear set of actions, there is a lot going on behind-the-scenes when a workflow executes. This can sometimes lead to some steps firing before other, earlier steps in some cases.
Which hints that the server-side actions default to using client-side values from the start of the workflow - unless they can be linked to a previous action.
The following outlines the most useful workaround:
Custom events run in sequence, not parallel. If Workflow 1 triggers a custom event that starts Workflow 2, Workflow 2 will complete before the remaining actions in Workflow 1 run.