This site (a) suggests that cocaine use can cause or exacerbate skin picking, sometimes recognised as "Excoriation disorder".
Another site (a) goes into a little more detail in regards to skin picking behaviours vs excoriation disorder, but that's not particularly important here.
And somewhat tangentially,
an article (a) describes increased risk factors for cocaine users developing OCD.
Skin picking can also happen due to heightened stress, giving a sense of "relief" not too dissimilar to self-harm, or just generally satiating a compulsion (of which is bound to return). Stimulants can cause compulsions or OCD-like behaviours, though this is typically recognised more with amphetamines.
Here's a couple of snippets from the aforementioned links that might give some insight into what might be causing Rekieta's pockmarked skin.
Whether his stress might be considered understandable or otherwise, there's no doubt that he's very stressed. There has been some inklings of paranoia, but some of his behaviours in that regard can be explained by his constant need to defy and prove others wrong.
And, from what I understand, he began his "substance journey" with the legalisation of marijuana in his state, which apparently can be an additional risk factor (in this example, when used alongside cocaine) for OCD, which can manifest as skin picking.
