I've not made any changes to the levels of the normal Dinosaurs that spawn. Is it possible your server owner changed the settings, or possibly you have just been unlucky?

the lvl cap on dinos on my realm is 80 for rexs. and i know a few spots where i occassionaly encounter them on the daily. my admin implemented the mod saturday and its now tuesday and i have only seen 1x 75+ normal rex. 99% of the rexs are 65 and below and anything 70 and above is a king/queen. maybe the kings/queen ovveride the chance of a rare high lvl dino to spawn? its just an observation as of now but my whole server has taken notice. was jw if you had any insight. kings/queens spawn where rexs/spino use to spawn. or maybe make a large rex thats a reg rex but with revamped colors that shrinks on tame so something is tamable.

Seen the same pattern, but I think it's more like kings kill the high rexes that spawn in the exact same area.. Kings are like all over, did 105k exp on a Quetz in one day.

Try adding,

DifficultyOffset=1

to "GameUserSettings.ini"
Which after a "cheat DestroyWildDinos" our server spawned in wild lvl 30+s as it should.

Note: This will make it like official servers were the lvl goes up to 120.