  Context. Highly excited molecular hydrogen H2 has been observed in many
regions of shocked molecular gas. A recently published $K$-band spectrum of
Herbig-Haro 7 (HH7) contains several vibration-rotation lines of H2 from highly
excited energy levels that have not been detected elsewhere, including a line
at 2.179 $\mu$m identified as arising from the $v$=2 $J$=29 level, which lies
above the dissociation limit of H2. One emission line at 2.104 $\mu$m in this
spectrum was unidentified.
  Aims. We aim to complete the analysis of the spectrum of HH7 by including
previously missing molecular data that have been recently computed. Methods. We
re-analysed the $K$-band spectrum, emphasising the physics of quasi-bound upper
levels that can produce infrared emission lines in the $K$ band.
  Results. We confirm the identification of the $2-1$ $S$(27) line at 2.1785
$\mu$m and identify the line at 2.1042 $\mu$m as due to the 1-0 $S$(29)
transition of H2, whose upper level energy is also higher than the dissociation
limit. This latter identification, its column density, and the energy of its
upper level further substantiate the existence of a hot thermal component at
5000 K in the HH7 environment.}
  Conclusion. The presence of the newly identified $1-0$ $S$(29) line, whose
quasi-bound upper level ($v$=1, $J$=31) has a significant spontaneous
dissociation probability, shows that dissociation of H2 is occurring. The
mechanism by which virtually all of the H2 levels with energies from 20,000 K
to 53,000 K is maintained in local thermodynamic equilibrium at a single
temperature of $\sim$5,000 K remains to be understood.
