I recommend you continue waxing. The necessary work is far more than it's worth and still risk's failure.

Poly has poor adhesion qualities compared to other finishes. If there's a lot of wax on there, you will have even more problems. While you might remove some of the wax, you'll not get it all.

There is one possible way.

Get all/as much of the old wax off as possible.

Apply a coat of one or two pound cut blonde shellac. That is the difficult part, since you will need to order the shellac and mix the correct ratio with denatured alcohol. Google shellac mixing and shellac dealers. You will need just one pound of shellac and not use all of that.

It will dry in an hour(unless the humidity is high).

Then apply the poly.

The reason that can work is because the shellac will adhere to the remnants of the wax and the exposed wood. The poly will then adhere to the shellac.

However, poly chips when damaged and to repair the damaged areas, you would need to sand the shipped areas smooth and apply another coat of poly to the entire top.

If you were to use a non poly varnish(from a real paint store), you can sand and touch up the damage as a spot repair by applying varnish just to the damage and feathering the repair.

Adding to Handymac's advice, it is crucial that a shellac barrier coat itself be wax-free (de-waxed shellac) and that you try to remove as much wax as possible first.

The only canned shellac that is de-waxed is Zinsser Sealcoat