Hi,
I am willing to do this work for you.
I can use TAPI for dialing and playing a pre-recorded message. I can use C# as the language to implement the project. I can use MYSQL/MS SQL as the database (or anything else you prefer). System can read from MS Excel/CSV as well. Also, I can incorporate 2 modes as you mentioned. Lets discuss and continue.
I worked as a developer for 16 years and now working freelance. Also, I have used .NET (C#/VB.NET/ASP.NET) fore more than 10 years.
Thank you.
Best regards,