I've looked at the code to see if I can figure out whats happening. So I'll talk about Seliph's example first then Ced's examples.
Sigurd is a master knight with major Ulir blood, Seliph starts as a lord. By the logic in the randomizer Seliph should be a master knight but because the master knight is a reduced chance class it re rolls, This seems to skip the able to wield holy weapon logic so Seliph now promotes into a forrest (Hero).
In Ced's cases its similar to Seliph's one, the randomizer is set to match parent (loose) and Lewyn is a fire mage in random 16 and a pirate in random 1, in both cases Ced either got baron, emperor, or master knight then the class got re rolled into dragon master in random 16 or bow knight for random 1.
I think all you need to fix this is to add a check to make sure that class picked from the re roll is valid for Seliph's holy weapon check and match parent (loose) for Ced as all the reduced chance classes are promoted classes as gen 1 doesn't need to be restricted except Quan, gen 2 either isn't bound to a unit in gen 1 (the statics) or this can't happen to them (the gen 2 children and substitutes).
Seliph's and Ced's example is random 16. https://www.dropbox.com/s/3me3w2y5ixzrm87/fe4%20random%2016.html?dl=0 Ced's second example is random 1. https://www.dropbox.com/s/jl2x1ygmghxdqyw/fe4%20random%201.html?dl=0 (ignore the file names I'm not good with coming up with names).
I've looked at the code to see if I can figure out whats happening. So I'll talk about Seliph's example first then Ced's examples.
Sigurd is a master knight with major Ulir blood, Seliph starts as a lord. By the logic in the randomizer Seliph should be a master knight but because the master knight is a reduced chance class it re rolls, This seems to skip the able to wield holy weapon logic so Seliph now promotes into a forrest (Hero).
In Ced's cases its similar to Seliph's one, the randomizer is set to match parent (loose) and Lewyn is a fire mage in random 16 and a pirate in random 1, in both cases Ced either got baron, emperor, or master knight then the class got re rolled into dragon master in random 16 or bow knight for random 1.
I think all you need to fix this is to add a check to make sure that class picked from the re roll is valid for Seliph's holy weapon check and match parent (loose) for Ced as all the reduced chance classes are promoted classes as gen 1 doesn't need to be restricted except Quan, gen 2 either isn't bound to a unit in gen 1 (the statics) or this can't happen to them (the gen 2 children and substitutes).