Pedo is Latin meaning "relating to children". The diver he's referencing is primarily known as the one that rescued the children. Thus by calling him "pedo guy" what Master Musk is doing is actually saying "the guy who is known to have saved the children". Honestly I thought he showed a lot of restraint. The diver will not live forever but the design of the sub will and could, as a result, nearly-but-not-really save many more trapped children in the future.
Sus is Latin and can mean 'boar'. When he put (sus) Sir Elon obviously intended to evoke this image, which is used as a symbol of courage in indiginous tribes and elsewhere.
Not really sure how anyone is reading that tweet as an insult. Perhaps instead of criticising someone that directly helps the world become a better place in everything he does, some of you should aim to be more like him and come up with devices that could solve problems but end up not doing.
*clap* *clap* *clap* . Bravo sir! We shall drink brandy on Mars some day with President Musk and laugh at the haters!