[speedball1]

Hey Todd, you say

Trap below the hub is confirmed

But I want to know exactly how it was confitmed? By listening at the hub when someone flushed a toilet?
You went on to say,

Couldn't get a stick or rod down there very easily due to a couple bends

Those bends concern me. The trap, unless it's a drum trap, should be directly under the tub waste.
You also told us,

but I stuck some paper towel on the end of the snake and it came back saturated.

How did you get the stick past 6the bends?
But this,

we've never had any sewer gas

plus Marks test has me convinced that there's something down there.
However, until the floor's opened up we'll never know will we?
Call me a old "fuddy-duddy but looking at the pictures and reading the explaiunations just doesn't smell right to me. I'm not disagreeing with any one but there's simply too much supposition going on here. If there's a "P" trap down there why are the bends there? And why was the tub hooked up like this in the first place. All due respect to Mark and everyone the chimed in, Ya-all are most likely correct. Todd will be just fine connecting direct with a cold lead and oakum joint, (shouldn't that be caulked with caulking irons?) but this fix just leaves too many unanswered questions for this old plumber.
Regards to all, Tom

[cpctodd]

Hey Tom. Two 90 degree bends back-to-back are just there to jog over from the tub drain to the cast iron hub. You can see them in the photo. (I went through the tub overflow to avoid breaking apart any connections, since I don't have materials, experience, or space to reattach.) The bends are enough to prevent a rod or stick from going down into the hub, but I used a snake with a piece of paper towel coiled into the end. No, we'll never know exactly what's under the hub unless I dig it up, but the evidence tells me there's some kind of trap. I think they just never sealed that joint with oakum and lead back in 1970.

I don't know anything about caulking irons. I was just planning to clean out the hub as best I can without removing any piping, pack in some oakum, and fill the last 1" with Soil Seal when it arrives - no place in town seems to carry the stuff (or even know what it is) so i ordered it online. I'd probably pay a plumber to come fix it "per code" but the last one talked about breaking the concrete to get working room and said it would cost thousands of dollars. Plus general consensus in these posts is that oakum and soil seal will work just fine. It seems the only issue would be if a plumber comes out to fix another problem, sees something he considers out of code, and voids a warranty fix by claiming an "improper installation."

[speedball1]

I was under the impression that the bends were under the cement and the hub was part of one of the bends. Since you have it open have you put a rod down there to check for a trap? Although I can't explain why there's no tub dap-out and why the hub's above the floor this might be the hub end of a cast iron "P" trap. I also wonder why there's a offset to connect in the first place, After you've established that there's a trap down there make your connection as Mark described. Good luck, Tom