  We reinvestigated the neutron multiplicity yields of Ba-Mo, Ce-Zr, Te-Pd, and
Nd-Sr from the spontaneous fission of $^{252}$Cf; by (i) using both
$\gamma$-$\gamma$-$\gamma$-$\gamma$ and $\gamma$-$\gamma$-$\gamma$ coincidence
data, (ii) using up to date level scheme structures, and (iii) cross-checking
analogous energy transitions in multiple isotopes, we have achieved higher
precision than previous analyses. Particular attention was given to the Ba-Mo
pairs where our results clearly confirm that the Ba-Mo yield data have a second
hot fission mode where 8, 9, 10, and now 11 neutron evaporation channels are
observed. These are the first observations of the 11 neutron channel. These
8-11 neutron channels are observed for the first time in the Ce-Zr pairs, but
are not observed in other fission pairs. The measured intensities of the second
mode in Ba-Mo and Ce-Zr pairs are $\sim$1.5(4)$\%$ and $\sim$1.0(3)$\%$,
respectively. These high neutron number evaporation modes can be an indication
of hyperdeformation and/or octupole deformation in $^{143-145}$Ba and in
$^{146,148}$Ce at scission to give rise to such high neutron multiplicities.
