I question whether any part of this arrangement can be considered a gift. The money was sent to you with "strings attached." The money was never really yours to do whatever you want with it, even though it was briefly in an account in your name. It was given to you with the requirement that you would use it to buy a car that would not be yours. And the car was not a gift from you, because you never owned it, and the money to purchase the car was never really your money. It seems more like some kind of business transaction than gifts.
If the money wasn't a gift to you, it seems that you would not have to file Form 3520. That form is required for money you received "that you treated as gifts." If you didn't treat it as a gift in any way, it doesn't seem that you would have to file Form 3520. There might be other reporting requirements that I am not aware of. It might be a good idea to consult a local tax professional who is familiar with international transactions.
Aside from the tax and reporting issues, I have an uneasy feeling that this whole arrangement might be a scam, or some sort of money laundering scheme. It doesn't pass the "smell test." Is the friend someone you have previously known in person and have a long-standing personal relationship with? Why was the money sent by a company instead of by the friend himself or herself? How long ago was the money transferred into your bank account? Foreign transfers can sometimes be reversed many weeks later.
