Dear terrapots,
I can't quite 'see' what you're describing, but I do have a suggestion.
Go to your nearest yarn shop (an independent ) and ask for their help. I've never been refused, as they want your future business and knitters are as friendly as gardeners.

Here is a link that might be useful: find your way

That map didn't list any shops close to me but I remembered Beverly's holds knitting classes so maybe I can find help there. Thanks for the idea.

I made a sweater with similar directions once. And I agree that it would make sense to just continue down the front of the sweater. As I recall, I followed the directions and then whipped the collar edge to the front button bands. One simple way to do a button hole is to YO, k 2 together. Mark the sweater with pins for buttonhole placement. I prefer to buy buttons for sweaters that have a shank so the button has a little space under it to accommodate the thick fabric. I have also made my own buttons using yarn and a little ring around which you crochet sttitches to make the button. Cheap, and it matches the sweater perfectly.

You know, the collar may have a different number of rows than the button bands. If so, I can see why they might have you do the collar separately. So check the pattern before you experiment.

I'm pretty sure the button bands and edges are the same number rows as that on the collar ends. I was thinking maybe I should have started the collar in an inch from the end of the neck edge so that the 4 or 5 row knitted edge ended at the neck edge and then the button band would protrude beyond that. I was just studying my blouse and the collar ends that way so that I have a notch. But, too late, I'm not redoing anything. This was just part of my live and learn experience. Not something I plan to brag about, just that I'm actually finishing something significant, at least to me.

I was going to ask if the collar ends are flush with the front edges of the jacket and then I read your second post. It sounds like that's the way you knit them, but I agree with your feeling that they probably should have been set back a little. That would explain why the directions said to knit the trim strips on the collar and the jacket fronts separately.

If it were me, I'd probably reknit the collar. One reason you should do that is because the two edges of the collar will overlap when you button the top botton of the jacket. But since you don't want to reknit, go ahead and knit the edgings separately. If, instead, you knit them as one piece, the collar will not lay down flat. After you've finished the separate edgings, pin the collar down to the sweater so that it lies flat and, working from the outside (under where the collar will come), carefully seam the ends of the collar edgings to the ends of the jacket edgings. You don't want the stitching to show when you're done.

Doing that will both eliminate the "notch" (which I agree would look funny), and help the collar to stay flat. But you really won't be able to button the top and maybe the second botton. If you keep the collar sides spread apart, it should look OK.