kennedy's BIG tip

My malaysian friend Kennedy went to a restaurant somewhere nearby the hostel. He ate lunch there for 8.50 soles (like $3.) so he said it was a new restaurant and he tried to get change for his 100 soles bill ($40) but they didn't have change. So he tried to just leave a $20 US bill but they said no how can we change that. So he left the 100 soles and walked within 3 minutes and turned one time to the right and came to the hostel. That was 3 days ago and he hasn't been able to locate the restaurant again. He spends a few hours per day walking the blocks around the hostel-one block he's gone 8 times and even goes in place and asks do you have lunch for 8.50 soles? and I left something and they say no, our lunch is 8 soles and we don't remember you. He says he's so sad that he gave such a big tip and wonders if they closed down the restaurant since it was so new. But everyday from 12-5pm he searches for the restaurant and plans to eat lunch there-WHEN not if he finds it. He says that he was so crazy to do something like that and he wishes he'd spent the money on something else-anything else-but he just lost it. I asked him how much per hour he thought his time was worth and he said, he doesn't care, he even wants to hire a taxi to drive him around the city blocks to search for this place. He can only remember that they had a counter and the restaurant had 2 sides to it and it costs 8.50. In fact yesterday, I went wandering around with him looking for it and asking random people on the street if they knew of a restaurant that was new that sold plates for 8.50 soles. It's this funny runny joke now and today he has a cold but is getting ready cuz it's 11:56am and he's got to start his afternoon search for the place. He leaves in 3 days so he's getting a bit desperate to get his accidental BIG tip back. He has a big smile and sense of humor about it but being a gambler he just can't cut his losses and enjoy the rest of his time, he just keeps searching for the rest of his change.