Many thanks to Warren Hollinger for creating this route and sharing his tracks/writeup - I don't think I would have found this route otherwise, and certainly would not have persevered all the way to the summit if I didn't know someone else had already done it!
I started at 11:20am which is pretty much the worst time possible - it was very hot and sunny, and I quickly overheated on the roads. There was also quite a bit of traffic that time of day. If you attempt this route do yourself a favor and start very early in the morning - sadly my schedule didn't permit that. Luckily I got a bit of cloud cover and things started to cool off about 10 miles in. The steep pasture road section was cooler than the last time I was in the area (maybe a week prior) so that was nice. The fence traverse section was not my favorite - it was very overgrown and beyond what I would call bushwhacking - I just had to force my body through all these bushes with sharp branches, maybe I could have worn more protection but my legs were pretty cut up by the end. Once you dive into the jungle that was a lot more fun - sadly my gpx tracks were completely off, and I didn't find the trail at all for the first 20 minutes - it was just pure jungle scrambling and trying to link up game trails. I lost a ton of time there and then when I finally found the trail, I got turned around a few times before realizing you had to descend a very steep cliff area to link up to the actual Kohala summit. Once I got my bearings I was able to follow the trail easier - there are plenty of blue flags - but note those flags also mark other nearby trails so it's easy to get mixed up. That section was very boggy and I was up to my knees in a few mud pits. I was running short on time but finally managed to scramble up to the Kohala summit - it doesn't look much like a volcano anymore, but I liked it. I turned around, promptly got lost for 10 minutes, and eventually stumbled out of the jungle and made my way back to the road for pickup. Overall it was a fun adventure, I highly recommend it!