Eu tentaria a ferramenta de recuperação de bitlocker
You can use this tool to help access encrypted data if the hard disk has been severely damaged. This tool can reconstruct critical parts of the drive and salvage recoverable data. A recovery password or recovery key is required to decrypt the data.
Para o Windows 7, a Microsoft tem alguns conselhos
The BitLocker Repair Tool (Repair-bde) is a command-line tool included with Windows 7 and Windows Server 2008 R2. This tool can be used to access encrypted data on a severely damaged hard disk if the drive was encrypted by using BitLocker Drive Encryption. Repair-bde can reconstruct critical parts of the drive and salvage recoverable data as long as a valid recovery password or recovery key is used to decrypt the data. The Repair-bde command-line tool is intended for use when the operating system does not start, or when you cannot start the BitLocker Recovery Console. If a drive has been physically damaged, it may not be recoverable.
Esse tipo de experiência demonstra a importância de fazer um backup diário de dados importantes em um disco rígido externo ou em outro computador. Provavelmente vale a pena fazer cópias ocasionais em DVD e armazená-las em um prédio separado (em caso de incêndio ou roubo).