Regarding the Olympus walkthrough, I conducted an experiment and found that you need to follow a different path than the described walkthrough and it will be more logical and correct, regarding dialogues and quests:
1. From Tartarus to the Metro station, where Bono will say that you need armor and direct you to the Dogs of Sunset, and Rodno will answer that you need anti-rad for your father.
2. We go to the PZ and there we get a substitute from Karl, and Ursul gives us the coordinates where to get the robe.
3. We go to the Mangy Dog, on the way to him, or back, the Rainbow will open, it's difficult to miss)) there we buy anti-rad from the Healer or complete Kent's quest, for which he will give you anti-rad, at the same time we take the plunger from the box, in the second building to the right of the entrance to the location.
4. We go to the station. The Metro and from there to Tartarus are all easy to complete, honestly, without cheats or edits. You can take quests along the way and complete them if possible.
I mean, complete those that don't require collecting any items, while those that do can be completed later.
5. Overall, I was able to return to Tartarus and cure my father on January 5, 2208, or two months later.
6. And another thing: the quest from the Screamer can be taken and completed at any time, not during the Olympus quests, as stated in the walkthrough.
Game walkthrough:
TARTARUS - the transformer can be repaired independently, using the scientific method of poking and prodding.
The New World Order is one of the most interesting locations in the game.
Sunset Dogs - there are three merchants here, one with different armor.
Laivos - access to Laivos is easy during Sam's quest.
Rainbow is a buggy location; quests sometimes don't start, sometimes they don't turn in right away.
Olympus can be reached in two ways: through Tartarus and through the main entrance in the armor replica.
Source: nuclear-city.com.