B&S Flathead 28M707 vs 284707 Crankshaft differences (pre 95' vs post 95'?

I was pondering opening my broken 99' 284707 flathead engine and replacing the piston/rod & possibly crank from a 93' parts motor. I know the rod is broke but I have a spare w/piston.
If I do need to replace the crank, the part numbers do not match up and I do not understand why. They are both 28 series side valve engines and they both have sleeved cylinders w/stock ring gap. The 99' broke due to a massive oil leak from a bad bottom crank seal which went un-noticed and the 93' broke due to a damaged/stuck valve seat which eventually threw the intake tappet into the block and cracked it open and made a mess/cam got all messed up with it.

So, The crankshaft I have on hand is pre-95 w/rod and piston from a 1993 28M707 that I am parting out (cracked block).
The engine I might be able to fix and get going again is from 1999, it is a 284707 but the parts fiche has a different crankshaft p/n.

Briggs and Stratton Crankshaft 693653
Used Before Code Date 95080100

Briggs and Stratton Crankshaft 693944
Used After Code Date 95073100

Does anyone know the difference between the two crankshafts?
(Basically putting a pre 1995 crank in a 1999 shortblock).
Will they interchange?

Thanks for any tips.

They are both flatheads. The engines are both 28's. No idea what you are saying. One version has no balancer? Lol.

You sir, should not quit whatever day job you have.

Not the same engine, not the same cam, something is off.