Did you click on the link I posted?
There are only 3 hits on this page. ( You can easily narrow down the number of hits. I put in "Robert Spencer" AND Gloucestershire. You need the inverted commas and the AND in capitals. It's the way the search engine works).
One is Robert Spencer about a 'messuage and land in Farmington' dated 1603 - 1625.You can only view this at Kew (TNA), or get a copy.
A second one is the will of a Robert Spencer of Tortworth Gloucs dated 1655.
This one you can download for free or get from Ancestry.
He may or may not be related, but you have to cast the net wide in research at the time you're looking at. It may give some clues to a family of this name.
I'm not sure about the 3rd hit dated 1673.
It about 'Gloucestershire Parish deeds', but then says they're in Monmouth.
Robert Spencer is a witness, so it wouldn't give you any more information about him I'd think.
If it was me I'd disregard that one.