Creatine mono can raise DHT which could potentially cause acne
I don't see anyone dosing Mono at 20-30g ED, nor would they like to for that matter.
Acne is a complex beast that can be triggered by a myriad of variables, hormonal (LH, Test, Prolactin, Estrogen spikes), Hygiene (sweat can be an issue) , viral acne, genetic predisposition, a stress reaction from the body (some people get flares of acne when they get stressed), some kinds of aerial facial herpes-like infections...
It would be really hard to determine if your pre is directly the cause for it...of course one could always infer (more like guess) the connection with those aforementioned reasons, which are not all the reasons for that complex beast called acne...