I agree with Gill's comment on the middle names; these often point to the conflation of individuals.
I found this old journal article on JSTOR. The Brent Family (Continued)
W. B. Chilton
The Virginia Magazine of History and Biography, Vol. 14, No. 1 (Jul., 1906), pp. 95-101 (9 pages)
https://www.jstor.org/stable/4242785I
https://www.jstor.org/stable/4242785
It appears to quote Anthony a Wood when outlining Brent's life. Wood was an antiquarian but importantly a contemporary of William Brent (recusant and lawyer) . He mentions his education said to be at the English Catholic College in St Omer, his admission to Grey's Inn, his marriage without issue to Barbara______ and her death. He states that he died in London on 21 May 1691. It would be important to find the original source of this quote.
The admission of William Brent son of Richard to Grey's Inn was in 1629 https://archive.org/details/registerofadmiss00gray There is a burial two days after the date given for his death of a William Brent Esq at St Giles in the Field Holborn in May 1691. Sharing image
William Brunt is said in your notes to have married in 1624. If the bio in the article on William Brent is accurate then these cannot have been the same man.
In my experience it would be very unusual for a married man to be admitted to one of the Inns of Court. ( A tiny number of practising attorneys were admitted later in life to enable them to plead in higher courts).Moreover, the article also says that William Brent was 80 in 1691 making him b circa 1611 and therefore about 18 at entry in 1629. This was about the 'normal' age of admission for someone without a degree. (And as a Catholic he couldn't go to Oxford without repudiating his faith) He certainly couldn't have married at 13 (1624).
Edit found William the recusant's profile
https://www.wikitree.com/wiki/Brent-348