The easiest would be to just shell out and type and pipe to find.
Code:
break on
$A = 'C:\FileA.txt'
$B = 'C:\FileB.txt'

$ShellCMD = '%comspec% /c type "' + $A + '"| find /i "' + @WkSta + '"'

Shell $ShellCMD

If @Error = 1
 'Computer ' + @WkSta + ' not found in ' + $A ?
EndIf

$ShellCMD = '%comspec% /c type "' + $B + '"| find /i "' + @WkSta + '"'

Shell $ShellCMD

If @Error = 0
 'Computer ' + @WkSta + ' found in ' + $B ?
EndIf
_________________________
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