Possible, but we need to refer the values twice (Arguments and App Resources). As far as @ClaytonM 's question is concerned , why not save the Page name using your activity in App Resources at the beginning of of every workflow ( as 1st activity) that way we always have the page name of Last accessed Workflow.
System.Windows.Application.Current.Resources("wfname") = wfName
In the catch Block you can get the workflow name as below
strErrorWf = System.Windows.Application.Current.Resources("wfname").ToString