Stool sample Tests

My son has a runny stomach since last week, we took him to our GP on Saturday 21/11/2015 who advised us to take his stools sample to hospital(Glynnwood) to be tested. My girlfriend took the stools to Lancet lab on Monday 23/11/2015 but was told that they do not have a do not have a quote for Kids. I called Discovery and spoke to Raisa who told me that as long the test is mentioned on the Key Care form it is covered, called again after the lab advised that they require authorization and spoke to Sara who told me that it is not covered however decided to escalate to seniors after I asked how come I get two different answers from the same company. I then received a call from Ashlyn who confirmed that it is covered and gave me a call reference number ***. I took a day off and took the samples to the lab yesterday 24/11/2015 left the samples and now we are told that they Discovery won't pay. My question is FAECIAL MC&S is on the Key Care Pathology Request form 2015 why can't you pay instead of all the long calls that are costing me a fortune. I am on a Key Care it is on the for why can't you cover.S