Get-AdfsRelyingPartyTrust -Identifier sydle | Set-AdfsRelyingPartyTrust -SigningCertificateRevocationCheck None -EncryptionCertificateRevocationCheck None
Should work just fine. Maybe that's not the actual identifier but the name. Try the following:
Get-ADFSRelyingPartyTrust | Select-Object name,Identifier | Out-GridView -Title "Select a relying party" -PassThru | %{ Set-AdfsRelyingPartyTrust -TargetIdentifier ([string] $_.Identifier) -SigningCertificateRevocationCheck None -EncryptionCertificateRevocationCheck None }
It will all your relying party trusts in a graphical table, you select one or more and click OK. Then it will disable the checks for all selected relying party trusts.