Thanks for the advice Espen!
The "quirky" thing is that I got TTL for a few shots with the exact (and new) sync cords, etc that I have hooked up now. So the TTL worked for a few shots and then didn't work for many shots - without changing any sync cords or plugs or anything - back to back. That is curious.
I've got the 5pin socket plugged into the correct place inside the housing per the Subal drawing in the Subal instruction manual. So it is wired 5pin to 5pin. And the hotshoe hooks in fine, I don't want to alter anything in the hotshoe as that would void my Subal warranty.
The Sea and Sea TTL unit works in manual bypass now with the TTL unit turned on. It used to work in manual bypass and TTL for a short time, but now no longer in TTL with late flash firing. Flashes were fired at least 30secs apart or more so it isn't a case of the 110 strobes not being ready.
Yes the brand new sync cords could be bad but then I'd think they wouldn't then work in manual either hooked up to the TTL unit? I switch to TTL, it doesn't fire in sync, I turn the switch to manual bypass and they fire fine immediately.
Ryan from ReefPhoto is sending me a replacement Sea and Sea TTL unit and I'll test that out next week. Ryan really stands by the products he sells and recommends and I really admire that about the way he does business. I know it is not his fault the Sea and Sea unit isn't working right! 
If the replacement unit doesn't work I'll just go back to manual use of strobes without the unit as I can't stand things that aren't reliable. Plus the instruction manual for the Sea and Sea TTL unit says the unit is "positively buoyant by approximately 200g (7.1oz.)", when actually it is 6 ozs negative in-water weight. Water weight of my rig concerns me, especially the heavier d200 rigs, and I don't see how a company like Sea and Sea could get away with stating that their unit is positive when it fact it is negative in water. I was told this was a mis-print in the Sea and Sea TTL manual and on the specs but it is still mis-representation of a product.
As you see I'm not very happy with the Sea and Sea TTL unit, but it is nice to have the TTL so I'll give the new one another try right away and return it if it doesn't work and go back to manual strobe operation.
Plus I'll send this TTL unit that isn't working back to Ryan and he can see what is up with it. I'll let you all know his verdict.
Thanks, Carol
BTW, the exif data says the flash did not fire in TTL but the exif does say the flash function was present. Again in manual by-pass of the TTL unit there is no problem firing the flash and the exif data says flash fired. As far as I remember the flash icon did light up on every TTL shot in the viewfinder, but I'll check that again. The flashes did fire on TTL, but too late to be recorded in the photo/data, with lots of time in between flashes, on over 200 TTL flashes.