The embassy is insisting that although Bitcoin is legal in the country, they cannot accept it as proof of funds. The guy is a little bit frustrated because he is been forced to sell his coin prematurely in other to present the amount they are requesting. The visit is for an important business where he needs to test run and evaluate some equipment he wants to acquire. Taking a loan might not be appropriate since the embassy wants to see the flow of cash and not just a lump sum.
In that case, for me I think generating your address transaction via the Blockchair explorer would have been a better idea while using your Bitcoin wallet address, because it is exactly a typical example of a statement which shows an inflow and outflow of steady income, because he could tell those people that he works in an online firm, whereby he is been paid weekly through Bitcoin, as could be shown in this statement below which I was able to generate via using Blockchair explorer.
This might even worsen the whole situation, imagine showing someone that has no idea about Bitcoin won't even understand anything here, and secondly implicating yourself, if this is to be my country and you present a proof of funds via Bitcoin transaction, it can even attract so many questions which might even lead them to investigating and delaying the whole visa process and may think you're into some sort of online scamming when you present to them this blockchain transaction. This friend of his would have no option in case this is all the money he got than to liquidate some amount of Bitcoin greater than or equal to the amount of money requested to approve his visa .
Best thing to do in that situation is to ask the officers if they are accepting bitcoin as proof of funds. If in case they didn't accept bitcoin then one thing his friend could able to do is to withdraw his funds from bitcoin then use it as a proof so that he could go on the country he want.
Also this is good article to read regarding on the topic what OP want to raise here
provably that this could give an idea to people who got confuse about rules implemented by the authorities.