OK, lets look at it a different way. Lets just assume you have 15’ total of this drip tube for 2 trees. That means 7.5’ per plant? This tube has emitters every 6", so there will be 15 emitters for each tree, pushing .52 gallons/hour each. So each tree is going to get 7.8 gallons per hour. If you flow sensor is picking up .7 gallons per minute, then you have a leak somewhere I think…
Now, if we plug that 7.8 gallons into the drip emitter calculator that @azdavidr created (using my systems figures - gallons of water to be applied and inches of water applied in a flex daily schedule), I come up with .47 in/hr. MUCH closer to what I would expect to see from micro drip irrigation. There is no way that the 1/4" emitter tubing you linked is going to supply enough water to those trees in a 1 minute watering.