The violation point is DFW, not BOS. Returning from PVD is just as back-to-backy (new word) as returning from ELM.

Returning to DFW or its coterminal of DAL (if AA flew there) is prohibited.

You can return to HOU, SAT, AUS, TUL, etc. and fly Southwest or Delta to Dallas.

Or you can buy the tickets and take your chances. If you go that route, you may as well save yourself some trouble and not bother with PVD, unless you were going to Providence anyway.