  The requirements for hadron polarimetry at the future Electron Ion Collider
(EIC) include measurements of the absolute helion ($^3$He, $h$) beam
polarization with systematic uncertainties better than
$\sigma^\text{syst}_P/P\le1\%$. Recently, it was suggested to utilize the
Polarized Atomic Hydrogen Gas Jet Target (HJET) for precision measurement of
the polarization of the $\sim$100 GeV/n helion beam. At the Relativistic Heavy
Ion Collider, HJET serves to determine absolute proton beam polarization with
low systematic uncertainties of about $\delta^\text{syst}P/P\lesssim0.5\%$. To
adapt the HJET method for the EIC helion beam, the experimentally determined
ratio of the beam and target (jet) spin correlated asymmetries should be
adjusted by the ratio of $p^\uparrow{h}$ and $h^\uparrow{p}$ analyzing powers
$A_\text{N}^{ph}(t)/A_\text{N}^{hp}(t)$ which, in the leading order
approximation, is predefined by magnetic moments of the proton and helion,
$(\mu_p-1)/(\mu_h/2-1/3)$. However, to achieve the required accuracy in the
measured polarization, the corrections due to hadronic spin-flip amplitudes and
due to possible beam $^3$He breakup should be considered. Here a more accurate
analysis of the possible breakup corrections to the measured $^3$He beam
polarization is provided. The results confirm that the breakup corrections are
negligible for the EIC helion beam absolute polarization measurement by HJET.
