Will I not be able to descend with an airfoil that stalls at -0.5°?
Don't believe everything that a computer tells you.

This airfoil is listed in the airfoiltools site, and I took the liberty to copy its XFOIL results here:



I selected the Reynolds numbers 500,000 and 1,000,000, which should be at the low end for a man-carrying aircraft. As you can see, the stall angle of attack is at 15° and the maximum lift coefficient is between 1.7 and 1.75. To achieve a lift coefficient of 1.89 with that airfoil will need a much higher Reynolds number, but max. L/D is already around 120.