So you're just now getting ready to apply your second coat of primer? If so, I'm not really sure you really need two coats of primer, just one coat with full coverage. Though some say you don't actually need any primer at all with this paint.

To answer the orange peel question, no, successive coats will not "fill in" the orange peel finish. And since your primer is gonna be a different color than your main coat, you wanna get that primer as smooth as possible, to avoid sanding through to it later on while wet sanding your main coat and having it show through. If this happens, you'll have to repaint these areas and this is a huge hassle best avoided.

Also, how much time are you allowing the paint to dry? Are you sure it's completely dry? I like to wait until the paint is completely hard to the touch, and not the slightest bit rubbery at all, to where my hand slides smoothly over it and does not "drag" even the slightest bit. And also, the areas of thickest coverage won't leave score mark when I press in with my fingernail.

For me, this can take as long as a week, but some people have said that I'm putting on too much paint and / or not thinning it out enough. I get orange peel no matter what I do, so they may be correct.

Good luck and it sounds like you're being very cautious, which is a good attitude to have since mistakes made early on can come back to haunt you, like when I allowed my primer to drip, and some of these drips are still visible, even though I'm done painting now and waiting for my last coats to dry completely prior to buffing.