My friend sent in one of his guys a certified person with complete tools and he plugged in a gauage, indeed it was around 10 on dial. He replace the refrigirant and on the gauge he made sure it tops at 6. He said it should be adequate, near the factory amount.
Your right it was proper procedure to transfer the refrigirant to tank even here.
Nice thing about asking a friend with a reputable company the service I got was correctly done and it was free.