Your lower photo shows a very nice healthy amaryllis. However, the top photo shows an amaryllis which has some problems. That red on the leaves is most lightly an indicator of disease, not sunlight scald. That level of spotting and streaking is usually not fatal, but it does reduce the quality and quantity of blooming. There are fungi, bacteria and even viruses that cause different types of red streaking. It might be coincidental that you started seeing the problem, when it was in direct light, which is why you thought that it was sunlight scald. You can try treating it with a garden fungicide, dry it out a bit, and even, if you have to, cut back the diseased leaves. The good news is that the bulb itself doesn't look bad at this point, it looks like a leaf issue at the present time so it is worth trying to save it. Amaryllis should not be kept permanently in low light, they won't bloom.
