This question is kind of hard to articulate. If a person dying and becoming a ghost is something that happens in the Alpha Timeline and has to happen no matter what for the Alpha Timeline to succeed, but then later on there are OTHER offshoot doomed timelines which happen AFTER that person has already died (And which have nothing to do with that person dying), are there alternate versions of that person for each doomed timeline which happens after their death in the Alpha timeline?

No, a person that dies does not get an additional ghost for each doomed timeline that happens after their death.