Sorry about your friend. That is part on the risk we take, whenever we decide to put ourselves behind the bars.
On the other hand, I am glad to hear that you are going through EL Salvador. I am Salvadorian, and the I can tell the route you decided to take is one of the best ones. curvy roads, scenic views once you get into El Litoral driving "next" to the ocean. If you have time, you can also check the volcano of San Salvador (is not the active one)
which is about 40 minutes from El Tunco. There are few nice restaurants in that area such as La Pampa Argentina, Las Brumas, Café San Fernando in case you want to stop by one of those.
If you want to surf, I will suggest to try EL Sunzal, El Zonte or Km59, which are very close to each other with small hotels/hostels to stay. The locals in El Tunco noticed how tourist has grown over the years, so they decided to "modernize" the infrastructure, and raise the prices for food, drinks and accommodation; which IMO lost the fun part of what el tunco used to be. Still fun, don't get me wrong, but quite expensive compared to some other areas.
We just has presidential elections last weekend, so don't be surprised to see a huge amount of advertising, campaign, papers, and all that crap all over the place. We are going to the second round in a month, just so you know.
I hope you have fun in "El Pulgarcito de Centro America" if you need more info, or something that I can help just send me a PM.
BTW: try to avoid the city ( San Salvador) between 11am-2pm and 4pm-7pm is just a circus and a real challenge to drive.
Que se divierta!