Custom script extension incorrectly processing input characters

Question

Hello,

Custom script extension for Windows seems to be incorrectly processing characters passed to it. Relevant portion of my script extension is below

"commandToExecute": "[concat('powershell.exe -file ./consolidated-webserver/server.prep.ps1 ', ' -clients ', variables('convertedJSON'))]"

variables('convertedJSON') contains string with various characters which is correctly passed to extension which can be seen by examining file under Status folder as seen below

"powershell.exe -file ./consolidated-webserver/server.prep.ps1 -clients ^\"{'clients':[{'clientName':'dominos','sqlreference':{'keyVault':'dominos-urbumyyogx-kv','fdqn':'venio-dominos-sql.eastus.cloudapp.azure.com'}},{'clientname':'boeing','sqlreference':{'keyVault':'boeing-c4uujz4qkc-kv','fdqn':'venio-dominos-sql.eastus.cloudapp.azure.com'}}]}^\""

Actual powershell instance is launched though with following parameters -

Host Application: powershell.exe -file ./consolidated-webserver/server.prep.ps1 -clients {'clients':[{'clientName':'dominos','sqlreference':{'keyVault':'dominos-urbumyyogx-kv','fdqn':'venio-dominos-sql.eastus.cloudapp.azure.com'}},{'clientname':'boeing','sqlreference':{'keyVault':'boeing-c4uujz4qkc-kv','fdqn':'venio-dominos-sql.eastus.cloudapp.azure.com'}}]}

which you can see is missing ^\" characters