Dear christophers35608510,
If you disable External Link i.e. Set trackExternalLinks=false, the action wont be accounted as Exit in Adobe Analytics. In other words, Adobe wont count that exit navigation as 'Exit' metric.
If you want only one server call, you can add custom variables in the default Exit Link itself. Read this thread to understand more in detail : How to pass custom event with exit link in DTM
Thank You
Arun