I assume it ISN'T starting?

Check the oil level in the crank case and SMELL for the presence of gasoline.
It sounds like the carb needle/seat is leaking through, running through the cylinder and into the crank case.

we discovered oil and gas in the transfer tube and muffler. cleaned it as well as carb, still no go.

Remove the spark plug and GROUND the plug wire. You DON'T want spark!
Crank the engine over a few times and blow the excess gas/oil out of the combustion chamber.
You might have to clean the spark plug.

You have to-
1. FIX the leaking carb problem or at least install an inline shut off valve
2. Change the oil

Don't bother changing the oil, it's a 2 stroke. Probably a leaking float valve in the carb but I'd also ckeck for a good spark while I was at it.

can't see a spark, with plug out and grounded to the head. new plug and nothing. what else could it be?

The module is bad. I am just is the process of replacing, for the second time, the module on my 10323 with Duraforce motor. It's 8 years old.

Yes, when the float sticks in the carb, it'll run rich and carbon-up the transfer pipe and muffler, then shoot black gunk out of the muffler. It'll also sit there and leak down a whole tank of mix after you put it away.
1. First, get an inline gas shut-off and install it.
2. Get a new ignition module and install it.
3. Bounce the back end of the mower a few times to shake the float loose.
4. Start adding 4 oz of Marvel Mystery Oil to 2 gal of mix in addition to the regular oil.

This should get you going and keep it running right. Remember to turn the gas off everytime you put it away.

What else could it be?
A bad switch or out of adjustment cable on the deadman lever, not very likely though. I'm with Bogman on the coil being the most likely. I think I change coils more oftem than plugs.

i have had luck on putting those coils in the oven at a low temp and drying them out. used to do it once every 6 months (or anytime we had a good rain storm ) on my duraforce

The fact that you have already gotten 11 years out of
that mower, speaks volumes. You have obviously taken
fairly good care of it.

If ya ain't got spark, fix that first, then move on
to your other issues, as outlined above.

Unless the wheels are fallin off, or the deck is rotted
out, go ahead and fix it up. Your other option is to to
go out and buy one of todays mowers, and spend upwards
of $700, and get nowhere near 11 years of service out of
it. YMMV.