Thanks for your question
This seems like a scam as the Bank of Eng;and would NEVER ask for money on behalf of the government, can you tell me more about this please.
Or money laundering - so is this a person you know in real life, are you or your friend UK citizens - are you saying you have to pay out the £5000 in the hope you then are paid back?
Please be careful here and provide more information
This is a scam I am afraid - just type into your search engine (Google etc) South African scams - they range form Inheritance tax, lottery wins, helping out a friend etc
All of which start off with you needing to pay money before your large promised amount can be released - it is made worse because your friend may genuinely have a South African father who has does within the last few years
But money is NEVER asked for up front and certainly not from a UK source such as the bank of England or the UK government
I can certainly see your point of view but no one other than HMRC or a UK solicitor on the instruction of HMRC (with tax payable to HMRC) would ask for money prior to release of funds.
So something is not right here - but I am happy to wait for some further information