Don't Overthink Your Aiming
OK so, I know that this can be tricky to do, as, on many occasions, you do need to rely on good aiming on the course in PGA Tour 2K21. With that being said, Divot Derby is a game that is all about speed, and speed alone, so scores, shot quality, etc aren't a concern here.
Simply just swing away, and this can give you an advantage. If the winds are high, you may have to quickly adjust yourself accordingly, but other than that, it's an all-out swing fest. It's preferred that you avoid the rough and hazards, of course, but don't worry if you do so.
Even if your ball does land in the rough, sand trap, or water, you can still actually qualify for the next round and eventually win. That's one of the beauties of this new mode; even when things seem bleak, you can still advance to the next hole if you're quick. Now, if you feel like you can still be very fast, even while using aim a lot, then, by all means, go for it. However, if you find out that it's slowing you down, then just close your eyes (not literally) and unleash chaos on your golf ball.
Try Avoiding three-Putts
One key thing that will help you advance in Divot Derby is on the green. The putting in PGA Tour 2K21 is highly popular for its overall realism and authenticity. the realism will remind you of what they say about the sport in real life; try avoiding three-putts.
The same goes for in this fast-paced game mode. You can still qualify if you do, but it will be much harder, and so, drilling a putt in two shots or less will give you an edge in battle. Also, take this tip as not just trying to avoid three-putts but also a reminder that it's OK to two-putt.
Even when two-putting, you can make it to the next round plenty fast. As long as you don't spend much time reading the green, you'll be alright. Try to get the ball as close to the hole so you can just tap it in and get out of there comfortably. Of course, if you hit your second or third shot close the cup, then you'll be in tap-in range anyway. Or, you can drill a long-range putt. If you do that, then awesome, you have a great advantage.
Don't Fret on Your Current Ranking
So this is just more of a mental note, and those can always be good for a sport like golf. But don't fret if you aren't in the top five after qualifying for the next hole. It doesn't matter where you end up, so long as you qualify.
Sure, you'll get some minor recognition if you finish a hole as the top dog, which is fun, but at the end of the day, there's no advantage. It seems obvious, but in case there is some confusion, it doesn't affect anything; it's really just a number.
I had played a round and barely qualified after one of the holes. I would then proceed to (somehow) win the event. So, in short, don't make an end all be all priority to place in the top three to five after a hole or two during your Divot Derby experience in PGA Tour 2K21. Just play as fast as you can and hope for the best and of course, have fun because it is a great mode.