PATHWORKS for Macintosh is a Digital product. It is sold and supported by Digital. The official line from Digital is that they only support their version of TCP/IP.
You won't be able to get all the components to work if you don't allow DECnet protocols, since most of them rely on DECnet. The most common thing people use TCP/IP for is MacX and DECwindows; if you use another package, you need to make some adjustments for this to work. For instance, you will have to log on to the VAX via Telenet, and under VMS, create a display for DECwindows with the $ SET DISPLAY command. You will have to know what parameter to specify for /TRANSPORT because the keyword TCPIP is reserved for the Digital TCP package. After you successfully create the display, you may use the $ SPAWN or $ RUN/DETACH command to execute the DECwindows client over the display.
The bottom line is that you will have to work with both Digital and Wollongong to get the correct syntax for different operations. If you are very interested in running PATHWORKS in this environment, we suggest you discuss the situation with the Digital Account Rep for an official Digital solution.