Oop's made a little mistake, it wasn't an Armstrong who preached to the Jacobites but Mr Patten.

From the book Northumberland-Yesterday-and-To-day
http://www.fullbooks.com/Northumberland-Yesterday-and-To-day1.html"Not far from the village of Catton, the name of "Rebel Hill" reminds us
that it was a vicar of Allendale, Mr. Patten, who joined young
Derwentwater in the rising of "The Fifteen," and was appointed chaplain
of the little army. He met some half-dozen men of the neighbourhood at
this hill, when they set off together to join the rest of the forces at
Wooler."
The Murray's of Tullibardine where Jacobites.
The other Hollin Hall's in the area were:
Hollin Hall just outside Bishop Auckland, which would be too far away in your case. Hollin Hall , Fir tree, Wolsingham, which would be too far away and The Hollin's outside Ebchester which would be too far away to be described as outside Blanchland/Hunstanworth.
This leaves the other Hollin Hall in Catton, Allendale which is more than likely the Holland's Hall that you have referred to, which locally is classed as near/just outside of Blanchland/Hunstanworth.
I have two theories why it may have been known as 'the Barons'
1) From the days when the Bishop of Durham granted the lands/Manor of Allendale which they became the Lords of the Manor, these were also known as Barons.
2) It may be that your Murray's may have decended from the Murray's of Tullibardine and were known locally as 'Barons'
Regards
Rewcastle