Okay, by the numbers:
Asking a vet to kill a police officer, in defense of a low-level gambling operation, would be idiotic. Vets, even employed in illegal enterprises, respect police officers and killing one would be Dishonorable. If CW doesn't understand this, and is covering up or fleeing from something drastically more criminal than the skatepark, then she may have just been that idiotic, but if so it raises her personal risk from Bubbles getting violent more than it does that of Officer Lilac, and she ought to realize that. It's not the sort of thing she'd ask if she intended to be around Bubbles much longer.
Having a cop killed is not something you do unless you fear being caught for something with a penalty equal to or greater than that of a cop killer - which mostly boils down to serial murder, or running an enterprise in which you have committed or ordered multiple previous murders. In a few states large-scale drug dealing where there have been multiple deaths from overdoses or drug violence will do it. This doesn't describe the skatepark operation but who knows what else CW is doing, has done, or what the semi-illegal skatepark may be a front for.
Also, CW is likely to have means of escaping much more reliable and less risky than any possible hit on a police officer. This may involve faking her own death and murdering one of the other AI at the skatepark to have his/her drive replaced with her own and taking over his/her life. She may have even done something like that before. Why do you think they call her 'Corpse Witch' after all? Officer Lilac may be investigating an earlier murder, or several.
Posing as one of the employees she most likely wouldn't even face jail time or back taxes, and might be off parole in 60 days or less. This kind of murder is MUCH less likely to be detected (hence much less risky) than a hit on a police officer and MUCH more likely to solve long-term problems because nobody is going to be trying to prosecute CW's crimes if they think CW is dead.
This leads to an utterly horrible scenario. The easiest and most advantageous of lives to take over is that of a repair mechanic who rarely goes out, has few friends or attachments outside the skatepark, and who probably wouldn't even be prosecuted because if she hasn't even been getting paid, she'd be treated as victim rather than criminal and released immediately. This would be a plausible reason why CW has been pressuring Bubbles to NOT develop interests and friendships outside the park; such attachments would make her life more difficult to take over. Finally, the easiest murder to plan and execute is the murder of someone who relies on systems you ultimately control for functions such as power recharge, replacement parts, and backups.
And that leads to another utterly horrible scenario. The main barrier to taking over Bubbles' life - the main risk of being caught - is the attachments Bubbles has formed outside the skatepark. Attachments whose death would then become a means of reducing risk.
I'm a suspicious bastard. When dealing with known crooks, it's the best policy.