we have used the "kids nite out" service twice now. you can choose the general description/type of babysitter/companion you would like to care for your children.
if i had a nine year old whom you seem to think will object to a "babysitter", i would request one of the younger/cooler folks and give them permission to take your child down to the arcade. bet that makes her happy.
as far as how good they are, i certainly feel safe with them. my daughter who was leaving her 9 month old with a babysitter for the first time in her life agreed to do it based on her opinion "if there's anyplace that's going to make sure their babysitters are good, it's disney."
the first time we used the service, we swore Mary Poppins arrived in our room. she opened her little bag and out came a slew of interesting toys and books. she just kept taking out more and more stuff, till we asked her if the floor lamp and umbrella came next!!!!
the second time we used them was last month, by now my daughter had a 3 month old and 2 year old. this one was not as good. she certainly was adequate, we felt safe leaving the kids with her, but Mary Poppins she was not. we told her that the 2 year old is rarely allowed to see tv, so if she turned on the tv, he would be entranced, and should be entertained for a good length of time. we then went into the dressing area to finish up, came back out and she had BASKETBALL on the TV. we explained to her that we sort of meant a DISNEY CARTOON, you know, mickey mouse clubhouse, little einsteins, something visually appealing to a 2 year old.
i relate this story to say........i guess it's hit or miss, some are Mary Poppins and some ain't!
but no matter what, i would feel safe and i am sure a young/cool "companion" would be satisfactory to your 9 year old
go out and enjoy yourself