Few quick lube places may be cheating customers in charging for no work had been done, or over charge for synthetic while using dino or HDEO, but it is very hard to believe that they would put 15 quarts of oil into a car engine. Even all of the workers at this quick lube work there the very first day when this happened, they do own some cars or SUV's and they should know the average sump capacity. They also have computer to enter customer info to get the oil filter, they should see the sump capacity right there.
I don't mean that I don't trust OP, be his friend may be confusing in sending the text message.
I don't mean that I don't trust OP, be his friend may be confusing in sending the text message.