Store mills are commonly set fairly loose so the grain may not have been crushed very well, my grain is very fine bits, almost to a powder with the husks intact, the finer the grain is crushed the better to extract the sugars.
After the hour mash you added the volume you lost to absorption back at 212 degrees, let it rest for 10 minutes and drain into your kettle, then you added the final water amount to the grain and stirred and drained, that was your sparge addition... I split the volume into two seperate steps, so I would add in 1.75 gallons stir the heck out of it and let it sit for 10-15 minutes, vorlauf until it's running clear, and drain into the kettle, repeat with the second sparge volume of 1.75 gallons, stir, rest and drain....
Running the volume through the grain again was likely counter productive, you are trying to extract the sugars from the grain into the water, (think osmosis to an equalibrium between sugar level in grain and sugar level in the water. Which is why I do multiple sparge steps to continue to extract sugars) by adding back your full volume of wort to the grain you were taking high sugar level water and adding it to the grain that had most of the sugar leached out of it, so you were adding sugars back into the grain.