How can I shoot better at a rave event?

I recently shot an event for someone I know who was a DJ for rave event. The event did not have any crazy lasers or anything just basic club moving LED lights and a fog machine going. The fog machine was pretty heavy and along with the moving LED lights and the overall dark environment, I had trouble with my focus all night and I ended out the night with a ton of blurry out of focus pictures that I had to discard. A lot of moments that I couldn’t get great pictures for because my camera was just focus hunting forever.

For reference I have a Sony A6700 with a Tamron 17-70 F2.8 and I tried to shoot in shutter priority mode with the shutter around 1/200.

I also shot some flash photography with a cheap speed light flash off amazon in Manual mode at F4 1/15 while the fog was lighter in the place and those came out perfect.

Any tips on what I could do to improve for next time? I was still able to get good photos that everyone was happy with but there many photos that would have been great if they were in focus and many moments that would have great to capture if my camera wasn’t hunting for focus. I am open to any suggestions, I just want to improve for next time and be prepared so I can capture all the moments I want.