At any given point, your second opinion study is supported and managed (academically, intellectually and administratively) by atleast three radiologists from TeleradiologyHub. TeleradiologyHub has highest L4 Panel, that has international board which should have atleast two radiologist from different countries. One can expect more conclusive results from L4 panel hence they are expensive. The general composition of members of all study panels is based on factors such as skills, years of experience, seniority, rapport, publications, internal ratings and earlier reviews, factors of communication and other parameters therefore setting up the panel is complex job and happens to be responsibility of working RRP during those hours. 

Also, clients may have difficulty forming a panel on their own since they may not know who is available or who has the required skills or who is open to work in team. To address these concerns, the RRP selects experts (L3 or L4) based on the client's needs, including budget and time constraints. The composition of the panel will not be changed once it is set. (You must also read Second Opinion: Terms & Conditions). The category of experts (L1 or L2 or L3 or L4) will be told to client but not specific member details for the reasons of availability, data security and confidentiality.  

However, clients can still express their preferences from the over publicly listed 450+ radiologists by searching and little due diligence (Public Profile Visible here: Team of Best Radiologists), they can forward the profile and the RRP which will make attempts to contact the selected ones on their behalf. However, there is no guarantee that the preferred radiologist will agree to participate in the second opinion study.  4 out of 5 times it is a futile and uncomforting exercise, hence it is advisable that the RRP be responsible for creating Expert Panels for clients.

Additionally, some good and popular radiologists have private profiles, which are not visible to the public. The RRP is the only one authorized to contact them.