Serious question; could you clarify this? Does the team need any supporting evidence?
Yes, they are supposed to provide supporting evidence along with their application for a TUE. The requirements are set out in the UCI guidelines, but they are a bit vague. In the not so distant past, the only evidence required in practice has been a note from the team doctor: "Dear Mario, Bradley is feeling very poorly, please can I rub some cream on his bum? Love, Geert"
The DCMS have suggested that Wiggo's TUE was not required on genuine medical grounds, which implies that the supporting evidence was either falsified or non-existent, or just not checked rigorously enough by the UCI doctor.
Or do you mean
"the question in the public/fans minds is ... "
I have no insight into the process, I'm only considering the known facts. It's the DCMS who have raised the question about the legitimacy of Wiggo's TUEs, even if they don't understand the implications of what they have said.