When I was little (late nineties), I used to have a big book filled with short stories about dinosaurs, mostly sci-fi and a few of them having to do with time travel. I remember it having a lot of illustrations.

I'm pretty sure one of the stories was set in a world where people paid to go back in time and wander around a prehistoric landscape, and the main character, a man, met a woman who claimed she'd let the capsule she traveled in go back, and decided to stay behind. She almost convinced the guy to let his capsule leave without him, but he ended up coming back to the present, where he found the woman, who then confessed she'd just gotten there before him and had time to explore, which made her look like she knew the area well.

I don't remember much more about it, sadly
Can anybody help? Thanks in advance!