When you send an email with the request for a read receipt, that is all it is, a request.
The email recipient and their email client application are in total control of whether to send a read receipt back to the sender.
It does not matter if you are using VBA, .NET, or any other programming language to send the email with a read receipt request, it is still totally up to the recipient and their email client whether a read receipt is sent back to the sender.
if you send the email in HTML format, you could use a tracking pixel. Depending on the recipient's email client application settings, it might work. It generally works better than a read receipt request.