In a recent trip to Las Vegas to play poker, I also visited a former
business acquaintance who was having a trade show there. She stays in
the house of her partner's relative which is quite far away. In the
morning that I met her, she feels ill and desperately need to rest. I
secured a room with two beds and offer her to rest whenever she needs.
To make it easy for her, I even added her name as a guest during
registration (but I used only my name during reservation). The intend
is that she can get hotel help in case she loses her key or need
special assistance. So she rest while I was playing poker or helping
her to man her booth. A couple weeks after the trip, I find out she is
engaged (apparently not necessarily happily) to a man in Asia. Her
boyfriend/fiancée caught wind that there was a man she was seeing. She
believed that her wealthy boyfriend has hired a private investigator.
To avoid any misunderstanding (we did not do anything), I like to
ensure the registration and billing information is protected from
preying eyes. Can I have them even removed or suppressed? The hotel is
Treasure Island. I believe her boyfriend has my full name.

I plan to call the hotel soon. But like to know more before doing so.

Private eyes are great at finding out such information.

I have used them in the past (on behalf of clients) and I have been
amazed at what they can turn up.

I would assume the worst and arrange contingency plans accordingly.

The problem is that investigators use a method that contravenes the
usual safeguards to privacy. They bribe employees who have authorized
access to data and buy those data from them.

Most folks who engage in affairs don't use real names. If your
friend's fiance finds out about the situation, he will either be
annoyed that she may have had an affair or peeved that she's a moron
who is stupid enough to use her real name when supposedly sneaking
around (or worse, that she consorts with an idiot who would do that).

I think coming clean about what happened may be the best bet and would
short-circuit any accusation. Nothing would deflate a mental image
faster than a "Yeah, he got me a room 'cuz I was sick." A detailed
description of bloating and cramps from a particularly unpleasant
menses along with mild food poisoning involving shrimp will put off
any man. She can finish with "YOU were off flitting around half of
Asia with your mistress! Don't look so surprised, you know what I'm
talking about!"

I'd give good odds he is having affairs while away. It is the guilty
that has a suspicious mind.