I am not so sanguine. The platform cracked because it isn't thick/strong enough. You could glue it, but that won't be as strong as it was originally, and it failed. So the glue will, too. You could glue a piece of aluminum under it, and that might strengthen it sufficiently, but it will affect the looks, and the selling price, if you ever want to change.
If you don't fix it, eventually the cuing platform will start tilting, and the other side may break, and then you are really in a pickle - the cuing pot needs to be held tight, and I suspect the break was the result of an attempt to cure tilt in the past.
I speak as someone with a couple of JH/Mayware Formula IV arms with the same problem. No idea why the cuing platforms are so thin, or, if they need to be thin, why they aren't aluminum, not plastic.
800 bucks is real money (at least to me), and I'd want something that wasn't a potential problem for that amount. There are alternatives.