I'm afraid this is not good news. If you don't have the passcode or the bitlocker recovery key, there is no way to recover the data. Is it possible that someone made a note of or had the recovery key emailed to them? It's worth checking email accounts etc. Unfortunately for you, this is by design as Bitlocker would be pretty pointless if you could simply break into the data.
There may be specialist data recovery companies, but this is going to cost you a lot.
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