Hi there, DJG.
I found something interesting today...
Originally Posted by bulbapedia
In Generation I and Generation II, level 1 Pokémon in the medium slow group were calculated to have -54 experience points. However, due to the use of unsigned integers, the program took this to be 16,777,162 experience points, and if a Pokémon did not gain enough experience points to wrap this number back down to zero, it would be considered to be at level 100 (having gone over the amount required to be level 100 by over 15 million experience points), and instantaneously jump to this level.
It is due to this bug that no level 1 Pokémon can be found in the wild without abusing a glitch or hacking the game. It is also for this reason that although level 2-4 Pokémon can be found wild, Pokémon hatched from Eggs at level 5 when Eggs were introduced in Generation II.
This glitch was finally addressed in Generation III, which uses a lookup table, rather than an actual formula, to determine level-up experience (this is also why the two new functions introduced in that generation are able to be piecewise functions). Despite this, Pokémon still hatched at level 5 in that generation. Level 1 Pokémon were not "legitimate" until Generation IV, the first generation in which level 1 Pokémon can be found in the wild and Eggs hatch into level 1 Pokémon.
It is for the first and second generation but this may be the reason for level 100s and maybe even those level 10s in Sky Line...
Maybe the Pokémon have fixed exp that makes them 10 level and not enough exp for another level.
But since exp underflow occurs, raising them by using Rare Candy teleports them to level 100.
Dunno if it may help you somehow but it might be good to look at... here