The term "the odd" can mean "the occasional." It describes something that happens sometimes, but not too often. To "make the odd phone call" would mean that you occasionally make a phone call, but not very often. If you have a regular job at a bank, but you also occasionally teach lessons on Italki, you could say, "I work at a bank, but I also teach the odd lesson on Italki for extra money." It's a colloquial term. In context, it sounds like to "run a load" is to bring a load of cargo from one place to another, in a vehicle. (We can sometimes use the word "run" to describe an errand or task, especially if it involves carrying something from one place to another. "Can you run this letter over to the office?" means "Can you take this letter to the office?") So the speaker is saying that he knows about some people who occasionally bring a load of cargo into Sudan.