Let's simplify the expression step by step:

(2x + 1)^2 - (3x - 5)^2

= (2x + 1)(2x + 1) - (3x - 5)(3x - 5)
= (4x^2 + 2x + 2x + 1) - (9x^2 - 15x - 15x + 25)
= (4x^2 + 4x + 1) - (9x^2 - 30x + 25)
= 4x^2 + 4x + 1 - 9x^2 + 30x - 25
= -5x^2 + 34x - 24

So the simplified expression is -5x^2 + 34x - 24. It doesn't appear to factor into (x+3)(x-3).