Such a sad report! You are correct, formula is made to be mixed EXACTLY how it indicates on the package. Thinning it out can be dangerous as can making it thicker. If anyone is having trouble affording formula to feed their baby I encourage them to tell their pediatrician. There are community resources to help!
Yes, quite sad. I can tell you from experience, though, many parents also get confused about how to mix formula! If you want confirmation, just call your pediatrician’s office and talk with the nurse to confirm mixing instructions.