If your first vac was actually good you don't need to evac and re-pull. A manifold is useless on mini splits, all you need if you're very careful is a hose with a shut off valve and the right adapter to connect for mini's (5/16) and a good thermometer. Your system may have a mode to enter into to add refrigerant so check the stickers on the service cover of the condenser (outside unit). Set mode or turn system on high cool. Connect everything, bottle upside down and purge air out of hose at service port connection . Then open the valve on the hose for 3-4 seconds then close it and check temp at the head. Keep doing this until you output temp is 55-58 degrees F. Just remember to only add a tiny bit then check, easier to do with two people. Make sure the bottle is closed before disconnecting, keep system on when removing the hose and do it quickly so you don't lose refrigerant.