You have probably already applied the nematodes, but they need a LOT of moisture. The best time to apply them is during a rainstorm that is likely to last a few more days.
Mowing in the heat will cause the browning, but water will cure it. You should have seen it come back around. If you are in direct sunlight, next time try to mow about an hour before sundown. I also like to water after I mow. Mowing in the summer is very stressful to the grass. The longer you can go without mowing, the better. Wait until your spouse complains
45 min per day is good for new sod for a few weeks. Now you just wean it off and onto the deep/infrequent plan.