If she is saying "call me" then she is saying it's ok to ask over the phone. Not too bright but it happens all the time. In any event, asking a ladies rate for an hour of her time is really not the same thing as asking her what services she offers for that rate.

There is nothing wrong in calling up a provider and asking her, "I just wanted to make sure I know what your hourly rate is for your time". You have every right to know what your cost will be. You are not saying anything inappropriately if you phrase the question as I articulated.  

Now if the lady says her rates are available on her website, then dont press her further and check out her site. In the case you have cited, she is inviting you to call her (although I have never seen that statement on a site) to ask for her special rates. So do just that; say, "I noticed on your website you are offering a special rate and wanted to make sure I understood correctly your companionship cost for your time prior to our appointment". You should get the answer you seek.

Its all semantics. You know why you are seeing her. She knows why you are seeing her. You just have to go through the session without articulating why you are seeing each other. It's all quietly understood.

When you meet, let her know you saw her ad on XYZ.  Make the donation match.  Be prepared that Special sometimes expire before your date...  but she should honor it if it does not say a expiration.  
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