247PSI

First I've ever heard of an aircon belt to melt into the timing cover and kill the timing belt and balance shaft belt - sounds like the worst thing that could happen actually happened. I suppose the aircon belt is on the inside of the harmonic balancer and if it were to let go it would be stuck between the timing cover and alternator belt with nowhere to go except melt into the timing cover and kill the timing belt - ouch

In any situation where you have timing belt failure youre up for cracking open the bottom end and having to undergo a full rebuild .This MUST ALSO INCLUDE a full crack test and rebalance of the crank, just incase it has cracked it!!! If your machinist cant crack test it then take it to someone who can as it is VERY IMPORTANT.

Its a good chance to swap out the stock items for forged rods and pistons, new bearings, rings, gaskets, waterpump, belts, balance shaft eliminator kit etc with a full bottom end balance. The head will obviously have to be sent away for a full inspection and replacement of defective parts.

I see every chance of an engine block teardown as a good time for a full rebuild for reliability and longevity Dont skimp or you'll only be as good as the weakest link and could end up losing money in the long run with another engine teardown and having to do everything all over again

I'm sure one or a couple of us Brissy guys could come over and check it out for you if you like.
I take it the head is still on the engine?

The aircon belt should not be able to get anywhere near the timing belt unless the balancer let go and ate a hole in the lower cover!
If the timing belt shat itself you can expect a head rebuild at the very least.
You would be best to pull the head and have a look for damage to the pistions.
Where abouts are you located? If we know where you are it is easier to help you out.
Can you also fill in your location details in your profile.
Thanks