You can't file a claim since 4 years ago:
However, please note that the period for filing proofs of rehabilitation claims in the Civil Rehabilitation Proceedings ended on October 22, 2018 (Japan time). Therefore, Users can no longer file proofs of rehabilitation claims via the System.
That interface is only for creditors that have been admitted by the trustee and have received their credit numbers (code).
The real question will be how the money will return, is it Bitcoin or the value of Bitcoin at that time,
It's in BTC and each will get around 25% of their initial coins.