The poet here must be identified with Edward Johnson (b. 1592), educated at Magdalen College, Oxford, and the Inner Temple. Browne would have met him at either place. Both sets of commendatory verses for the Shepheards Pipe are from members of the Inner Temple.
From Of his Friend Maister William Browne, prefatory to Browne' the Shepheards Pipe (1614), sig. A3 ; repr. Poems of William Browne, ed Gordon Goodwin (1893), II. 81-2:
A Poets borne, not made: No wonder then
Though Spencer, Sidney: (miracles of men,
Sole English Makers; whose eu'n names so hie
Expresse by implication Poesy)
Were long vnparaleled: For nature bold
In their creation, spent that precious mould,
That Nobly better earth, that purer spirit
Which Poets as their Birth-rights, claime t'inherite:
And in their great production, Prodigall;
Carelesse of futures well-nye spent her-all.