How to access the spdsession object from a WebTransportSession

I would like to support getStats and sending goaway stuff in the node webtransport addon.
However, I am hitting the following problem.
GetStats and as well as sendGoawayHttps3 (needed at least from the server side) are available through the underlying QuicSpdySession.
However, it is a private member of WebTransportHttp3, so I have no way to access it from a visitor.
(My plan is to do a dynamic cast on the WebTransport object....).

Are there any plans to make these features available through the WebTransport base class, or at least to get access to the SpdySession?
(I think deriving a class from WebTransportHttp3 is not an option, since it is created deep within quiche objects?)
Or any hints, on how to do it in another way?
Thanks?