It very well could be 3 different people that have solved the last few keys.

Bitcoin isn't worth $3000 anymore like it was at the beginning of the year. Its almost $13K so the person who found the 1 BTC made alot of money.

Most people who visit this thread could be lurkers and they can have more knowledge than us and hardware. So there could be about a dozen or so people who are trying to find the remaining private keys. Its definitely worth the time.