First, I wonder what my experienced friends are trying to tell you. I get the feeling, they may be very successful(out of habit) but do not "know" what there doing. I am not being rude, but a real explination is to be had.
First, a female, must cycle in order to become gravid. If not, all the breeding(copulation) in the world will not make her become gravid.
When a female is in the first stages of reproduction(cycling) she emitts pheromones that intices the male to become interested and copulate. ALso in the first stages of reproduction, the female produces ovum, that turn into eggs. To drop the ovum, releasing from the overies is to cycle. Without eggs to fertilize, there is no reproduction, again, even if there is copulation. This is basic biology.
It appears your female has not cycled, as she is not enlarged the rear third of her body. This most likely means, she is not ready and their is no reason for the male to breed her. Most males will not even attempt to copulate a female that has not cycled. Of course this varies because of the goofy ways we keep snakes.
Of course, breeding and behavior is entirely based on having both sexes. Of course there are many bad jokes that could be brought up here. So if you know one, think of it here.
No, the male does not have to be larger then the female. I was the very first to produce albino Cal kings. In fact, your male is very similar to the original male. The second season of breeding albino Calkings. I used an eight month old baby male as the breeder. He was about 18 inches(if he was stretched) and he bred full grown mature adult females.(this was over thirty years ago, so its old information)
Also, it makes no difference which cage you put what in. Not to the snakes, only to you. In most cases, if you put the female in the males cage, he will either eat or breed whatever new is introduced into the cage. If you put the male into the females cage, many times the males feel the need to investigate this new area first, then copulate or attempt to copulate later. The difference is, in the first, copulation occurs right away. And in the second, you may not be patient enough to see it occur.
About sheds, this may or may not mean a darn thing. Under consistant conditions. You will get consistant results. That is, the relationship from hibernation to cycling and breeding. But of course, all you have to do is change the conditions or time of hibernation and that will change the relationship to shedding. Or if you understand that kingsnakes actually do not hibernate(thats a manmade sort of deal) and that cycling, a biological condition, is related to shedding, also a biological condition, but not necessarily related to a particular shed.
That is why you will hear, they will breed two weeks after the first shed, or right before or after the second shed, or any number of sheds. THese answers may or may not apply to how your keeping your snakes.
The simplist way to "know" when you female is ready to breed is, to observe. That is, to watch her. She will start with an unnormal fat buildup, in the lower third of her body(fat buildup). This occurs as the ovum is developing. At this time, she will emit phermones and become receptive. The female behavior is called Cloacal gaping. She will lift her tail on open her cloaca, when a male attempts to copulate. Heck, you can get her to do that, simply by touching the female and mocking the males movements.
Or avoid the above nastiness and palpate the female. To palpate is to feel for enlarged ovum or eggs. This is very very easy with kingsnakes(not easy with all snakes) Just let the female crawl between your fingers. Hold your fingers about a third less then the diameter of the snake and let her crawl thru on her own. To picture this, think of her crawling in a tight crack or hole(which they commonly do during their entire natural lifes) You will start by feeling a "string of pearls" which is the pea sized ovum that are a short distance from eachother.
When a female is fully gravid, it may be difficult to feel the seperations between the eggs. So the string of pearls is no longer detectable. At this time, you may only feel the seperations of only a few eggs.
As long as you are gentile, there will be no problems.
lastly their is a very very easy method to tell is she is ready and holding eggs. Pick up the female mid-body, and if she curls the lower third of her body, she is ready or gravid. This curling is the female protecting the eggs from moving out of place, She is using her body muscles to keep them in position.
I hope this helps and good luck, cheers