Help please: Sony A7RIV won't fire Inon 330s

Can anyone help me figure this out please. I have a pair of Inon 330s connected with a sync cable to my Nauticam housing using the Nikonos 5-Pin bulkhead and the universal hotshoe on an A7RIV but it won't fire the strobes. I've tried the following:

Connected the hotshoe to an A7RIII and the strobes fired (Flash settings on both cameras are the same) - so strobes and connections clearly work fine.

The A7RIV is firing a native speedlite and a Canon speedlite, which suggests it's not a problem specifically with the camera and/or hotshoe.

BUT the combination just won't work. Has anybody else had this issue and found a solution

Thanks

Solved, it was just a contact issue, corrected with a high tech solution - a rubber band to tighten the fitting into the hotshoe