cause if they've never worked together before, it's gonna be awkward.  If both know what's going on in advance, then at least each knows what's coming.

Usually, two providers that work a double are going to want to arrive at the same time.  The time shift will be a critical piece of information you will want to let both know.

If you're going to keep either party in the dark, you might have some unintended fireworks.

Bob

skip dinner

take them both to oxygen bar instead and get massages from girls

Personally I would love to be seen at dinner with a sexy lady seated on each side.

However, I do know that it can get expensive.  So I would say that it depends on the ladies.

I just recently set up what you are tlking about.  Two ladies I want to see are going to be visiting at the same time.  They are friends.  The offers a first night special, so I am picking her up at the airport to properly welcome her and take her to dinner.  I said I wanted her firiend to join us and she asked if it was for "dessert".  As per my first comment, we are stopping by the hotel to clean up & change, then all 3 heading to dinner.

Timing can also be a factor if you are only having the second girl for join for dessert.  You would kind of need to set a time, which may lead to a rushed meal or having to wait if dinner is quick.