...and going further back
Officially supported 9.4.3 upgrade paths:
9.3.2.0.11 to 9.4.3.0.12
https://support.ruckuswireless.com/do...
===========
Official 9.3 upgrade path:
9.1.2.0.8 and later to 9.3.2.0.3
9.2.0.0.138 and later to 9.3.2.0.3
9.3.0.0.87 and later to 9.3.2.0.3
https://support.ruckuswireless.com/do...
==========
and to get you up to 9.1.2...
"Only ZoneDirector 1000 and ZoneDirector 3000 with firmware versions 8.2.2, 8.4 and 9.0 can be
upgraded to this release. Upgrading from any other firmware versions might result in loss of
configuration settings"
https://support.ruckuswireless.com/do...
==========
So you possibly have several upgrades to perform.
Read those release notes and check the upgrade paths carefully.
Again coming from such a distant ZD version (9.0?) you would be wise to talk to tech support first.
Hope the detective work has at least woken you up!