How do I trace the Freehold?

A development of 4 flats/apartments were built in 2005.

The Developer sold the flats to a man who had a number of property companies though the properties were registered in his name.
On the sale of all four flats the Freehold (and management)of the flats was transferred into his name.
In 2011 one of the flats was sold before he was declared bankrupt.

The flats were repossessed and are being placed on the market individually. I assume they are being sold as the Tenants vacate.

The freehold is still registered in his name but with the bankruptcy recorded on the Land Registry.

I have searched the Insolvency Register but cannot find his details or any of his companies on there so I am thinking that he has been discharged.

Can anyone advise me of the next step in tracing who has control of the freehold.

I would be interested in buying all three flats buy it appears that no one has been maintaining the property as a whole.

The fourth flat is rented out and have no details of the Landlord.

Any advice gratefully received before I proceed further.