Cannot convert result form Invoke-Command to csv type

Hi to all . I have a problem with converting results from Invoke-Command into csv type. Code below :

$remoteResultEventLog += Invoke-Command -ScriptBlock {
Param ( [string]$EventLogName,
		[string]$EventLogEntryType,
		[DateTime]$EventLogAfter, 
		[DateTime]$EventLogBefore, 
		[string] $searchPattern, 
		[Boolean] $caseSensitive)

	$events = Get-EventLog -LogName $EventLogName -EntryType $EventLogEntryType -After $EventLogAfter -Before $EventLogBefore
	if ( $caseSensitive ) 
	{ 
		$events | Select-Object Index, Time, EntryType, Source, InstanceID, Message, PSComputerName, @{Name='Search Pattern';Expression={$searchPattern}} `
		| Where-Object { Select-String -InputObject $_.message -Pattern $searchPattern -Quiet -CaseSensitive}
	}
	else 
	{ 
		$events | Select-Object Index, Time, EntryType, Source, InstanceID, Message, PSComputerName, @{Name='Search Pattern';Expression={$searchPattern}} `
		| Where-Object { Select-String -InputObject $_.message -Pattern $searchPattern -Quiet }
	}
} -ArgumentList $EventLogName, $EventLogEntryType, $EventLogAfter, $EventLogBefore, $searchPattern, $caseSensitive -Session $serverSession

$remoteResultEventLogCsv = $remoteResultEventLog | ConvertTo-Csv -NoTypeInformation -Delimiter ";"

The last line give this error :

ConvertTo-Csv : Cannot bind argument to parameter 'InputObject' because it is null.

At C:\Temp\RemoteCheckTest\new\RemoteCheckFiles.ps1:131 char:65

+ $remoteResultEventLogCsv = $remoteResultEventLog | ConvertTo-Csv <<<<  -NoTypeInformation -Delimiter ";"

    + CategoryInfo          : InvalidData: (:) [ConvertTo-Csv], ParameterBindingValidationException

    + FullyQualifiedErrorId : ParameterArgumentValidationErrorNullNotAllowed,Microsoft.PowerShell.Commands.ConvertToCs

   vCommand

But Input Object in that case $remoteResultEventLog is not a null

Thanks for any answer