Connecting Remote Shares via Powershell
Alright, so this solution has turned out to be pretty ugly. The end result is that I have to run the powershell command via the Powershell job step type and run it using xp_cmdshell in a sql job step type. Running it in both contexts guarentees the drive is mapped.

I then run a secondary step for both environments in which I test to make sure the drive is mapped using the same logic, ie:

Sql (CmdShell) Check

exec xp_cmdshell 'powershell if(!(Test-Path -LiteralPath "W:")) {

    throw ("W: is not mapped")

}'


Powershell Check

if(!(Test-Path -LiteralPath "W:")) {

    throw ("W: is not mapped")

}