Authenticate encrypted seed for KEM + AEAD hybrid cryptosystem
It probably doesn't hurt to include the encapsulation as additional data for the AEAD, but there is no need.  The generic KEM/DEM composition,

\begin{align}
  &amp;(C_0, k) \leftarrow \operatorname{KEM}_{\mathit{pk}}() \\
  &amp;C_1 \leftarrow \operatorname{DEM}_k(M) \\
  &amp;\operatorname{return} C_0\mathbin\|C_1,
\end{align}

provides adequate security by the standard theorems, e.g. Cramer–Shoup 2001, Theorem 5 on p. 41.



You can safely separate the concerns of


generating the encapsulation $C_0$ and the key $k$ with RSA, and
one-time authenticated encryption under $k$,


as separate subroutines that communicate only $k$.

See Shoup's ISO proposal for more practical details of composition and instantiation with less math.



Incidentally, it is also unnecessary to generate an IV, since the key is used only once: you can safely use an IV/nonce of zero for the AEAD as a DEM.