Script not found in TFS Build Deploy Test

We have a pre-deployment script in our build that works and runs correctly when built and sent to a specific build controller and agent.

However, in the interest of streamlining, we've set up several Lab Environments and a build-test-deploy flow so that whenever a developer pushes a new build, it automatically builds the test methods and sends them to an environment for testing.

That part all works great and lovely and wonderful. However: The aforementioned script does not work in the build-deploy-test flow. It's got the exact same path as a machine-specific build, but every time we run the build we get

The system cannot find the file specified Exception Message: Team Foundation Server could not complete the deployment task for machine 'TestController1', script '"#/80908/drop/AutomatedTests/AutomatedTests.Desktop/ExternalLibs/GetEi.ps1"'

Here's the process parameters for the machine-specific build that works

And here's the process parameters for the build-deploy-test that does not find the script (And yes, I've tried without quotes and without $(BuildLocation))