Exactly. Having endured Ebola, he may very well have a an immune system that is compromised a bit.
No one really “recovers” from ebola, they survive it if lucky. Their immune system is handicapped for life. They become high risk for every bug going around.
That this guy is developing secondary infections is to be expected, very similar to people who die from the flu. It isn’t the flu that gets them, but a secondary infection that takes over.