Remote Powershell session not loading assemblies - powershell

Question

I have a powershell script file, that when executed via winrm, wont get executed correctly in some windows environment.
The below script executes fine in that machine.
$ssrsEndpoint = "http://192.168.10.1/ReportServer/ReportService2010.asmx?WSDL"
$ssrsProxy = New-WebServiceProxy -Uri $ssrsEndpoint -Credential (Get-Credential)
$ssrsProxy.CreateFolder("NewFolder", "/", $null)
but, if executed via powershell remoting, it fails. ("localhost" is coming from a variable, so i don't have control over it, if the admin choose to execute the script on the same machine, it becomes localhost. So please don't ask why I'm executing the script on local machine over winrm)
$iisSess = New-PSSession -ComputerName "localhost" -Credential (Get-Credential)
Invoke-Command -Session $iisSess -ScriptBlock { [void][system.Reflection.Assembly]::LoadWithPartialName("System.Net.WebClient") }
Invoke-Command -Session $iisSess -ScriptBlock { $ssrsEndpoint = "http://192.168.10.1/ReportServer/ReportService2010.asmx?WSDL" }
Invoke-Command -Session $iisSess -ScriptBlock { $ssrsProxy = New-WebServiceProxy -Uri $ssrsEndpoint -Credential (Get-Credential) }
Invoke-Command -Session $iisSess -ScriptBlock { $ssrsProxy.CreateFolder("NewFolder", "/", $null) }
`
+ CategoryInfo : ObjectNotFound: (http://192.168.10...e2010.asmx?WSDL:Uri) [New-WebServiceProxy], WebException
+ FullyQualifiedErrorId : WebException,Microsoft.PowerShell.Commands.NewWebServiceProxy
+ PSComputerName : localhost
You cannot call a method on a null-valued expression.
+ CategoryInfo : InvalidOperation: (:) [], RuntimeException
+ FullyQualifiedErrorId : InvokeMethodOnNull
+ PSComputerName : localhost
It looks like the session didn't get the proper assemblies loaded!
Any idea?
Environment
PS C:\deployments\> $PSVersionTable
Name Value
---- -----
PSVersion 5.1.14409.1005
PSEdition Desktop
PSCompatibleVersions {1.0, 2.0, 3.0, 4.0...}
BuildVersion 10.0.14409.1005
CLRVersion 4.0.30319.42000
WSManStackVersion 3.0
PSRemotingProtocolVersion 2.3
SerializationVersion 1.1.0.1
Pretty sure it is not the remoting configurations, see below the command running as a remote command.
[127.0.0.1]: PS C:\Users\Administrator\Documents> winrm get winrm/config
Config
MaxEnvelopeSizekb = 500
MaxTimeoutms = 60000
MaxBatchItems = 32000
MaxProviderRequests = 4294967295
Client
NetworkDelayms = 5000
URLPrefix = wsman
AllowUnencrypted = false
Auth
Basic = true
Digest = true
Kerberos = true
Negotiate = true
Certificate = true
CredSSP = false
DefaultPorts
HTTP = 5985
HTTPS = 5986
TrustedHosts = *
Service
RootSDDL = O:NSG:BAD:P(A;;GA;;;BA)(A;;GR;;;IU)S:P(AU;FA;GA;;;WD)(AU;SA;GXGW;;;WD)
MaxConcurrentOperations = 4294967295
MaxConcurrentOperationsPerUser = 1500
EnumerationTimeoutms = 240000
MaxConnections = 300
MaxPacketRetrievalTimeSeconds = 120
AllowUnencrypted = false
Auth
Basic = false
Kerberos = true
Negotiate = true
Certificate = false
CredSSP = false
CbtHardeningLevel = Relaxed
DefaultPorts
HTTP = 5985
HTTPS = 5986
IPv4Filter = *
IPv6Filter = *
EnableCompatibilityHttpListener = false
EnableCompatibilityHttpsListener = false
CertificateThumbprint
AllowRemoteAccess = true
Winrs
AllowRemoteShellAccess = true
IdleTimeout = 7200000
MaxConcurrentUsers = 2147483647
MaxShellRunTime = 2147483647
MaxProcessesPerShell = 2147483647
MaxMemoryPerShellMB = 2147483647
MaxShellsPerUser = 2147483647
[127.0.0.1]: PS C:\Users\Administrator\Documents>