First of all, you don't need to write $_{max}$ or talk about limits when it is *kinetic* friction. Kinetic friction has a fixed formula. That formula is:

$$F_r=\mu N$$

and not $F_r=\mu R$. Don't use the reaction force $R$, only the normal force $N$.

Now, this friction is what the ball affects the surface with. **It is *not* the *reaction force*, which affects the surface, it is the friction which does.**

The ball affects the surface with friction, and the surface holds back with the same force in the ball, yes. This is Newton's 3rd law.

> this appears to contradict Newton's Third Law, which clearly states that $F_r$ should equal $30 \cos(30)$. 

This is not correct, as I stated just above. The $30 \cos(30)$ is the reaction force's horizontal component $R_x$, but that is *not* the force that affects the surface. This $R_x$ causes friction, you could say, but they are not equal - Newton's 2nd law says that:

$$R_x-F_r=ma\quad\Leftrightarrow\quad F_r=R_x-ma$$

The $R_x$ is clearly larger than the friction $F_r$; the rest of $R_x$ Is used for acceleration.