But those aren't guaranteed, there weren't any in my game.

Basically asking other people where to pick up troops is a long shot cause every time you start a new game it randomizes 95 percent of the spawns of troops you can buy and most people have not played the game through enough times to know what exactly stays the same and what does not.

Typically though most people will carry some form of that race of troops on each play through very few will carry an absolutely completely different mob. For example if they had bowman and paladins first run same person may carry inquistors and swordsman next time staying with the humans and so with other races. So I usually remember spawns by what race of troops they carry on each play through cause it will usually be pretty similar.

Sure but Paladins are sort of a staple unit, most people use them most of the time so I mentioned them specifically. And it seems they are guaranteed at the Greenwort castle and/or Barracks but not anywhere else and since those two places are available only for a relatively short part of the game I recommend to buy them up all and store them at a safe place - probably Merlassar, viking islands or Freedom Islands.