SOLVED. Science fiction - virtual reality multiple worlds [s]

[Martin Wickman]

Book protagonist is an academic (professor?). They travel back and forth in multiple virtual reality simulations. World war is one setting. Jungle is another. There is an alcoholic father “nursing his squeeze bottle” and a African guy talking about “father mantis” or something.

[Lobstergirl, au gratin]

When did you read it?
Or when was it published?
Author's gender?
Cover?

[Martin Wickman]

Author is male. I read the book about 15 years ago. Can’t remember the cover.

The protagonist visits a bunch of these worlds, looking for something important. One world contains a giant.

Also there is a an important character living in a house with a health (skin, breathing?) problem so the house needs lots of humidifiers.

[Martin Wickman]

I figured it out! Otherworld by Tad Williams

https://www.goodreads.com/book/show/2...