Frequently at high temperatures tomato fruit will develop yellow blotches on the red skin creating an orangish color. This is a sign of high temperature stress and the pigments causing the fruit to become red are not produced evenly.

The tomatoes you had would never get sweet because they were not "old enough", or mature, to ripen and create sugars that are made in the ripening process. You would have needed a drop in air temperature and MAYBE the fruit would have then continued on to size up, mature and ripen. When temperatures get over about 95F, for most tomatoes, the chemical they produce to assist them in ripening, ethylene, is not produced or produced in such small quantities the fruit will not ripen or will not ripen properly.

However, if they are mature enough to produce ethylene Tomato Heat Stress on Fruit. Yellowing and uneven ripening due to a failure of the plant to produce ethylene evenly in the fruit. and it is too hot, then bringing them indoors will usually cause them to ripen. But if they were left outside and it continued to be hot they would not ripen. by Robert Morris