Run it like a Swiss bank ... all investors are just numbers, and management works via remote VPN, again, only numbers, with no way for the Russian mafia to find out who they are.  That way they won't be able to bribe nor threaten anyone or their families.  There will be a lot of money laundering, and other abuses, but if Putin wants the investments to come in, he will have to make the trade-off.  The investors could also set up a fund which would subsidize effective protection.  Maybe even hire former Spetsnaz to work with the police and army.