As reported on github issue: https://github.com/lvmteam/lvm2/issues/83 current lvm2 version 2.03.15 of lvm_import_vdo script does take wrong value for vdo_slab_size_mb value.
Solved upstream: https://listman.redhat.com/archives/lvm-devel/2022-June/024196.html https://listman.redhat.com/archives/lvm-devel/2022-July/024227.html