Is Inform and Ink usually used in conjunction with other engines though?

I believe Ink is usually used with Unity, yes. However, Inky, the editor written by the same authors as Ink, can export the story as a web page, like this example. I do not know how it compares to Twine, for example.

As far as i know, Inform is a standalone product and does not require the use of a separate engine. Of the two, Inform probably fits better with you profile. It also has an exhaustive documentation and plenty of examples; when you download the application, the documentation and examples are also included, and you can click an example and see it working. Other people have also written handbooks for it, although it is probably also true for Ink and the other engines.

As a writer / beginner solo dev, I probably only have enough bandwidth and patience to learn just a single engine and try make something with that vs trying multiple engines at once and putting it all together.

If you want an interactive story, i am afraid that some programming is inevitable, but, if you power through, at the end you will be comfortable enough to do what you need. We all have to do it when learning a new system, so at least you are not alone in that :).

Yesterday i found another interactive fiction engine called Windrift that made me think of you. Not because i think is the ideal engine for your case, as it is targeted to web developers, but for this mini decision tree i saw in its manual:

Windrift is not great at branching stories!
Windrift does not provide strong affordances for managing complex parallel plotlines—you can implement such stories in Windrift, but you'll have to manage this state yourself. If these are the stories you want to tell, look instead at a library like ink, which has first-order support for story threads that branch, join, and recombine.

Windrift does not have a parser!
There is no text input parser or world model in Windrift. If your story involves significant physical exploration or object manipulation, consider a parser-based game in Inform 7 or a similar library.

Windrift is not for novice programmers!
This manual and Windrift itself expect the author to be familiar with web development and software engineering. It's especially helpful if you are comfortable with JavaScript or TypeScript and the ReactJS framework. Novice programmers or people who want to just tell stories and not spend time on source code should start with the excellent Twine.

So, there you have it: Ink for complicated branching stories, Inform 7 for a deeper level of interactivity, or Twine if you prefer writing stories rather than source code.

I also wanted to share with you a commercial game written in Ink i heard about today: Werewolf: The Apocalypse - Heart of the Forest. I think this game is relevant here because, even though it has nice visuals and sound effects, it is primarily a text-based game where the narrative is king. I do not know whether it is the kind of games you want to make, but i believe is a nice example of a game that focus a lot more on the parts that you seem to enjoy.