Escrow is a small town in Überwald that had a problem with vampires...
The Mayor of Escrow had an invidious choice: submit to being effectively milch cows for the de Magpyr vampyre family or face the death of all the townspeople.
The resident witch in Escrow (ref "Annotation" below) is apparently a woman with a lot to learn about the Craft.(A recent graduate of the informal Lancre school?) Tiffany Aching describes her as a woman who tried, against all good advice and sound practice, to use magic as a short-cut to domestic cleaning, a chore more experienced witches tend to do long-hand as it grounds them in everyday reality. Apparently she got it wrong with the spell, and rather than clean her floor, the magic progressively took away the entire floor, the soles of her sandals, and finally one toe.
Features mainly in Carpe Jugulum.
On Roundworld the word Escrow means money, property, a deed, or a bond put into the custody of a third party for delivery to a grantee only after the fulfillment of the conditions specified. That is, a financial instrument held by a third party on behalf of the other two parties in a transaction. The funds are held by the escrow service until it receives the appropriate written or oral instructions or until obligations have been fulfilled. Securities, funds and other assets can be held in escrow.
In Wintersmith, Escrow is said to have its own witch. However, on page 182 (of the Corgi pb edition of Carpe Jugulum), the Countess De Magpyr explicitly states that "I was just going to say that there were no witches in Escrow". If the town were too far away from either Lancre or the Chalk to have had a witch before this, and in fact had none to guard and ward off vampyre intrusion, then after the events of Carpe Jugulum, you might lay a shrewd bet that Granny Weatherwax would have got somebody in place afterwards. Partly as a service to the people of Escrow and mainly as an "early warning system" to alert Lancre of anything unwholesome coming out of Überwald. It may also have been an excuse to get a student witch who listened too much to Mrs Letice Earwig out of the mainstream. Her catastrophe while using magic to clean the floor is suggestive of the classic scene in Disney's Fantasia, where Mickey Mouse plays the Sorceror's Apprentice. (Or, given the violence, the Itchy and Scratchy parody in The Simpsons)
In Unseen Academicals, we meet the suspicious Dr Able Baker, whose list of academic titles does not look anything like as impressive on closer examination. As at least one is conferred from Escrow, a small town which conspicuously appears to lack a cente of higher education, the suspicion is there that an enterprising Dibbler-like character resides here and operates a classic degree mill - ie, sells dodgy but impressive-looking academic qualifications by mail order.