3/4 inch through slot on router trouble??

You seem more savvy than me. But, FWIW, I would consider shallower cuts and the use of a fine rasp (near the front edge, since that is where you had issues).

Bill

The slot is to long for the table saw. I can use a mortise and tenon machine but was hoping to use the router table with one pass. I am going to use a 1/4" diameter router bit with light cuts to finish unless there are any suggestions. Thanks

Another thought. You didn't say what you were cutting. But if it is typical cheap plywood (i.e. not "Baltic Birch"), the "wood" may be to blame.

Can you use a dremell with an spiral cutting bit? OR of you have it a plunge router with a spiral bit?

Once you have the slot cut you could use a 1/4 straight cut bit on your router to clean it up.

Featherboards and stops. Don't let the piece go anywhere except where you want it to go and use enough friction that it goes at your speed.

If you have a small-diameter circular saw blade, two plunge cuts can define the sides of the slot; then a short bit of router work can trim the ends.

Turning the whole slot into sawdust seems a waste of time and energy. Starting with a half-inch slot is definitely wasting energy.