126.96.36.199.44 is the latest 9.8.3 ZD firmware. Check the Release Notes for that build, but it includes a bunch of bug fixes and was released specifically for customers with ZD 1100 or EoL APs that can't be upgraded past 9.8.3. (You are correct that you can't upgrade past 9.8.3 if you have 7962 APs.)
The 188.8.131.52.14 build you see there is the Standalone AP firmware, not ZD firmware. You need the ZD firmware.
Suggest that you keep a copy of the build that you know works, backup the configuration before upgrading, then if anything goes wrong you can always downgrade back to a build that you know works.
Hope it helps.