I have the same table. Mine has screws that come into the bottom of the
table and hit the bottom of the insert. You use these to adjust the insert
to bring it level with the rest of the table. I used a big machinist's
scale for this. It works perfect and it's right on the money.

Try that, and if your fence is still off, I would take it back. You should
be able to just take the angle brackets off and get new ones.