Can I do a 2- or 3-star alignment using the PMC-Eight ASCOM driver?

No, the PMC-Eight ASCOM driver does not provide a virtual 2 or 3-star alignment procedure or function. 
The driver expects the mount to be physically aligned with the North or South Celestial Pole (NCP/SCP). This is in conformance with the ASCOM Standard API. One of the assumptions that is part of the ASCOM architecture design is that any telescope driver assumes that the mount is already physically aligned with the NCP/SCP. The more accurate the alignment, the more accurate the mount tracking will be. Another assumption is that the telescope when attached to the mount does not have any Cone Error, and the RA and DEC axes are orthogonal, or at perfect right-angles to each other. 
This ASCOM API requires that any client application that controls the mount must provide the 2- and 3-star alignment functions if the ASCOM client application developer needs that function in their app.   The ASCOM Telescope driver API provides a SYNC function which is sometimes called a 1-star alignment and ensures that the mount is synchronized with the sky, like setting your watch to a GPS time signal. This SYNC function is needed for proper GOTO navigation and is independent of the tracking accuracy of the mount which relies on the physical polar alignment with the NCP. 
The ASCOM Standards platform provides a way for client applications, such as Cartes du Ciel, and MaxIm DL to connect to multiple devices without providing a customer device driver for every manufacturer. As you can imagine creating a client application that supports all the hundreds of devices out there would be nearly impossible. Since the ASCOM platform Telescope API is used on lots of mounts, certain assumptions are made about the physical configuration of the mount's design and how it is operated.