What exactly is not matching for h2? Did you do something different for h1? Looks like freqz returns the DTFT of h2 as it should. Well, at least the magnitude, I didn't check the phase.
h1 = [.5 .5];
h2 = [0.5 -0.5];
omega = -4*pi:0.01:4*pi;
fz1 = freqz(h1,1,omega);
fz2 = freqz(h2,1,omega);
figure;
subplot(2,1,1);
plot(omega/pi, abs(fz1));
grid on
title('Magnitude response of h1[n]');
subplot(2,1,2);
hold on
plot(omega/pi,abs(fz2));
grid on
title('Magnitude response of h2[n]');
plot(omega/pi,abs(h2(1)+h2(2)*exp(-1j*omega)),'ro','MarkerIndices',1:20:numel(omega))
hold off
