Bling!!! Cool module too.
It's so disapointing when you take the back off a watch only to find that some careless person didn't bother to take the dead batteries out of it 30 years ago.
Your replacement module might not be working in the Zodiac case because of battery residue or dirt on the pushers/backplate battery contact/backplate to watch case connection etc. Give all of the connections a clean (cleaning alcohol) and see if that helps. If the batteries make contact with the case and the pushers make contact with the module then it should work.
It's also worth checking that your replacement module isn't making a contact where it shouldn't. Put some electricians tape over the quartz and make sure that nothing live on the front of the module is touching the case.
(Of course "it should work" is a much overused phrase in this field of interest :wink: )