"I had sent a message to senator Scullion saying in your report please talk to Dr. Lawton, who is Gurrumul's doctor, and Michelle Dowden, his private nurse, who has helped him navigate the health system for the past 5-6 years".
Grose also says that Elferink has asked for a private meeting with Yunupingu, but the singer has declined the invitation.
Yunupingu is now waiting for the findings of an investigation by the Health Complaints Commission, an independent body that deals with complaints about health service providers.
"Because no-one knew who Gurrumul was, what you've seen is a really clear picture of what happens to the everyday ordinary punter off the street that goes into that system and has some assumptions made about them," Grose says.