With all due respect, i think it would be unfair to call the taxi company to start investigating about a sexual assault you have no idea whether or not it occured.
Such an investigation could put an innocent man in a dire situation possibly costing him his job and the stigma of being a sexual predator, regardless of outcome.
This is a serious accusation. If all you can remember is that you told him your life story, absent if any physical evidence of assault - what exactly are you going to achieve?
I understand you want evidence that you are/were safe to satisfy your anxiety, but this seems extreme.
If this is a pattern for you, perhaps it is time to re-evaluate your attempt at moderation and consider full sobriety like all of us in here. We're here to help you, take advantage of what this community offers.