I wouldn't worry about that; call it a design feature.
I can think of a few fixes for your cabinet:
1st & easiest, why not cut out the bottom and drop it the full 2" that's needed? You could suport the bottom with cleats attached to the base. That is, if the TV base is small enough to fit into the cabinet base. 2nd & do-able, but will alter the look a bit; knock the cabinet apart, cut off the miters, and a little more on the top, and add a block that will connect the top to the sides. You could radius the exposed corner, of make it from a contrasting wood. 3rdly, you might just have to make a new cabinet. At least it's a fairly simply design.You could offer the three options to the client and level with her; option one you'll do for free, option 2 will cost a little extra for the repair, and option 3 there's no way you can charge for another entire cabinet so you'll lose your shirt. Or, if you think option one will work and the TV base will fit into a dropped cabinet bottom in the base, tell her you've solved the problem, and it will actually look better because it will hide the base, and all you'll see is the tv screen in the cabinet.
Good luck, hope this helps. And next time, get the spec sheet for the tv before you build! >8^)
-- Timothy Juvenal
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