proper way to write g tube order in home care

I could really use some help. I take care of a child who falls under home care rules that attends a child care center for kids with special needs. This child takes most of her feeds by mouth but receives a continuous night time feeding. Her mother had asked if we could write an order on a PRN basis for when she is sick, or just does not eat well, etc. The order was written, Pediasure 1-3 cans per day, PRN per G tube. I was told that this was not correct and that we needed exact instructions and times. I argued the point that it is based on the parents instruction and also on nursing judgement. I gave the example of an aerosol that is PRN that we give it when we feel the child needs it based on our discretion. Could someone please help me find the correct answer? She says we are not using the 5 rights and I say we are. Please help!
You can't use cans and you have to explain PRN.Example: May give Pediasure 1 can (240 ml/can) per#14 FR Gtube every 6 hours PRN when child unable to eat PO. Give per bolus over 30 minutes.

Pediasure 1- 3 cans via g-tube prn for decreased po intake, I tried, but still don't like it...lol. But, the number of cans of pediasure are based on a specific number of calories required to maintain the child's health. How does her order for continuous feeds read? And is it going to be bolus or via the pump? See, one question leads to another. I would consult the dr regarding the order. You don't want to over load the child.

Pediasure 240 ml via G-tube at 12 noon PRN via (pump over X time or via bolus feed over x time) (or whenever lunch time would be) when PO intake less than 100% but greater than 60% of meal.Pediasure 480 ml via G-tube at 12 noon PRN via (pump over X time or via bolus feed over x time) when PO intake greater than 30% but less than 60% of meal.Pediasure 720 ml via G-tube via (pump over X time or via bolus feed over x time) at 12 noon PRN when less than 30% of meal.

Pediasure (*med) 240ml (*dose) per GT (via pump/time or bolus/time) (*route) p meals (*time) for PO intake < 50% (whatever % decided upon). NTE 720ml/24 hours.