You can never be to certain what other people are dealing with outside of work. Sometimes, management knows things that they are not at liberty to share.
Exactly. There are a vast number of incapacitating health related reasons that could cause a person to be absent, e.g. panic attacks, stuck in a bathroom (IBS/IBD/Chron’s), migraines, depression. The type of thing that reasonably wouldn’t be broadcasted out to the entire team.
I think it’s better to just assume nothing unless you have direct knowledge that the employee is doing something blatantly unethical like working at another job (has happened before).