As you know there's a huge difference between Northern California and Southern California shoreline environments. You said the sun gets hot, so I'll assume you're at least south of the Bay Area. If you're so close that you're affected by fog and salt spray carried in the wind that would add some complexities.
Summer solstice - the longest day of the year in the Northern Hemisphere - is June 21. After that the days start getting shorter. The difference is minimal at first. By late September the difference from one day to the next is at its maximum, and any outdoor annual plant will know that time is running out.
Cloning is something I know nothing about. Hopefully someone who does know will contribute. Having said that, it makes sense to me that a plant cloned indoors under 18/6 lighting could get very confused when suddenly set outside. Do you know anything about the cloning environment and the lighting schedule? Were you expecting it to go into flower so soon? A photo-sensitive pot plant in California that had spent all or most of its life exposed to the outdoor light cycle would not be going into flower this early.
What does dirt with chips mean? Do you have a brand name?
People have done far worse things to their plants than your topping efforts. I know it's hard, but you have to stop fixating on that. Forget about the top, as difficult as that may be, and concentrate on the plant's overall health.
Oh, hey, I forgot - I've read over and over again on RIU that you should stop topping a plant 2 weeks before flipping from veg to flower. I don't understand why your outdoor plant thinks it's time to flower but you need to put away the clippers and help her get to the finish line.
Or, as some of the guys said, maybe force it back to veg. But I think you'd have to take her indoors and crank the light cycle way up to make her forget about flowering and go back to veg. I'm sure there are limits to this. Once a plant has decided for sure that it's going to spawn and die like a salmon it can't be easy to turn it around. Doesn't matter, 'cause you said you can't do indoor so my uneducated guess is you're stuck with it trying to flower.
June 21 is almost a month away. Most strains have typical flowering times, expressed in weeks. I don't know how long Diamond OG is supposed to run, but if you can keep it alive maybe it'll flower for an extended period?