A lightning strike cannot be blocked by much of anything. I lost my entire security alarm panel a few years ago - same situation. The solution? Replace the entire panel.
Several things could have happened to the MacBook. One is that the RAM got fried. That would be easy to replace. There are other components on the mobo, CPU, capacitors, etc., that could be blown.
Trauma like this usually suggests sending it in for repair.
Lesson learned - always disconnect during a thunderstorm.