Verify value in text file

function ReadDateFromFile(){
  var sPath = "PATHTOFILE";
  
  // Opens the specified file for reading
  var myFile = aqFile.OpenTextFile(sPath, aqFile.faRead, aqFile.ctANSI);
  
  // Skips to the specifed position and reads the specified amount of symbols
  myFile.SkipLine(NUMBEROFLINES);
  myFile.Skip(NUMBEROFCHARACTERS);
  var sDate = myFile.ReadString(10);
    
  // Closes the file
  myFile.Close();
} 

The above script should work to get just the date from the file, then you can set it to a variable and compare it like any other variable.

Or use aqFileSystem.FindFiles to find a file by mask:

var foundFiles = aqFileSystem.FindFiles("C:\\FolderName\\", "FileName_*_*");
if (foundFiles != null) {
  if (foundFiles.Count == 1) {
    var sPath = foundFiles.Next().Path;
    Log.Message(sPath);

    // Read data from the file
    // ...
  }
  else {
    Log.Error("More that 1 file found.");
  }
}
else {
  Log.Error("File not found.");
}