Headline says it all!  I work down by the greenway and don’t know how to find a provider nearby.

I have been hosted at many locations close to The Greenway. Walking distance! (Or maybe a couple of subway stops if you're lazy.) The thing is, "The Greenway" is not as specific as a neighborhood, landmark, or intersection so it's not a used as a locator.
.
I suggest following a normal search for "Downtown" (or even "downtown Boston, NOT suburbs!"). THEN ask if the location is near The Greenway.  Note that touring girls or non-local phone help might not know what you are talking about when you say "The Greenway." But I think you'll find some great possibilities not too far from The Greenway.  
.
Good luck!

(One of my old stories. The meeting place was something like #10 X Street, a very long street, but I didn't remember the numbering. I asked the phone girl, "I know X Street! Is #10 at the end near landmark A or is #10 at the other end near landmark B?" She laughed at said, "I don't know! I've never even been to Boston! I'm in Georgia!")  
.
Here's a Boston Neighborhood Map. YOU will know where The Greenway is. The Greenway Maps I found were too cluttered and commercial. I you find a good one, post it below.

Any providers in downtown Boston hosting near PO Square.  It seems everyone is in Waltham!  

I don't have current ("today") info, but I have been hosted a few times at the former bank building, now a luxury hotel that directly abuts PO Square. I can only assume that you might find indies or agencies still using that location.

Probably by Vicky Brasil lmao Never actually saw her but I know where she used to be

Does she still host there from time to time? PM if don't feel like replying in public

Yup. Vickie B used to host there in an Airbnb apt.  She was a lot of fun.  She's been MIA for about a year

I'm Downtown Boston and offer Incall and Outcall and Would Luv to Meetup With You. XO

GiGi Amour  
857-523-6049.