I can't imagine an internet forum in the world where crowd sourcing a list of Subject Matter Experts would end well.
Perhaps we can create a list of members who are published authors and their work so we can judge for ourselves. I know we have several on this site.
I don't read nor do I understand this genre, but would a reader who will suspend their disbelief not accept that an 8 foot tall by 4 foot wide troll taking part in WW2 fits inside a Mossy?
Asking for a friend.
This is one of my favorite YouTube channels. Maxfiart scratch builds unique rubber powered free flight models. Many videos include the build process and all have excellent flying sciences.
https://m.youtube.com/@maxfliart/videos
Check out the example problems "Mathematics of Satellite Motion". Several of the variable have to be known in order to solve the equations.
Also, check out this link to answer your second question. Go to the "Orbit Manuevers" section to see the maths. Click on the embedded links for example...