I do not know the specifics about that case and of course i am not a physician but speculation that artery or tendon damage could cause complications or additional surgeries, or a secondary infection seem most probable for extended stay. Large teeth causing deep lacerating wounds, anticoagulant properties of saliva and possibility for introduction of bacteria all account for dangerous bite from a komodo. The point is moot however, a bite is dangerous from any large animal. Any animal including dragons host bacteria in their mouth, but it has been ruled conclusively that rotting meat between teeth causing death by bacterial infection in animals bitten by komodos has been ruled out, they have no more higher amounts of bacteria or more deadly strains than other animals sampled, a more likely source of infection and resultant deadly sepsis is when injured, the animals (wild cattle) retreat to mud water holes that have large quantities of the animals' own urine and fecal material in them.
Here is a zoo keeper bitten story where Dr. Bryan Fry (venom doc) talks about Komodos being venomous (anticoagulation properties)
This is the zookeeper bite
yeah the foot bite seems to have resulted in surgery
So these three bites in captivity actually just sound like regular monitor bites, with maybe the exception of the one where the bleeding couldn't be controlled. But then there was also this bite that occurred recently to someone well-known in the lizard community: https://www.youtube.com/watch?v=gmn4GGQaVuc. It's a bite from his monitor. This is the monitor that did it: https://www.youtube.com/watch?v=HtUB4d0CH_8. So not even very big.