I guess I have to end my silence.
Jeftichew's enemy is not Parson. It was never Parson. Parson did not take part in the attack on Unaroyal.
Jeftichew's enemies are Stanley (who he can't touch), Ansom (who lead the raid, but Jeftichew can never expect to get close to) and Wanda. And where can Jeftichew get to Wanda?
At the Gate from Gobwin Knob.
There is no great conspiracy here. It's just one man seeking his revenge on the person that destroyed his side. He spends his time obsessing on his vengeance and hanging out at the portal to GK in order to harm Wanda, who has been constantly at war since taking Unaroyal and so never in the MK. Parson was simply someone that came through and did something interesting, and may be a better mark than Sizemore.
For Jeftichew to be lying in wait for Parson as part of a conspiracy, we need to involve the Predictamancers to tell him it will happen, or else he could wait all his life. Predictamancers can't seem to determine when their Predictions will occur (at least, so far their predictions are open ended in time frame), so that means once a Prediction has indicated Parson will pass into MK, we have to add a Mathemancer to tell us when he will probably do so.
Many casters in the MK are concerned about Parson being in their Kingdom, since he might be able to force them to join his side (at least, that's the most likely reason I can see for their severe reaction to his presence), the Predictamancers might have made such predictions and bought the required services from the Mathemancers. That does, however, create conspiracy, and not amoung a group that seems particularly reliable at keeping secrets. A conspiracy of people that tell the future isn't going to last long.
So how does Jeftichew know about Parson? The situation in the MK immediately after Parson returned to GK made it evident that some in the MK knew about him, and wanted to ensure his survival, despite the paranoia of every other nearby caster that demanded his death. That is going to force people to make explanations -- where did he come from, how can he come to MK, why should we let him live, and worst of all, how do you know about him at all? A lot of powerful casters were going to need answers from the conspirators that created the scroll to bring Parson to Erfworld. Parson will, in the MK, become common knowledge, just to ensure he cannot steal people away by sneaking in.
Note that none of this requires Charlie. All of the knowledge of what and who Parson is is already inside the MK, so we don't need Charlie to explain it to anyone, and the opportunity, motive and means to commit this conspiracy are present without Charlie. Charlie is not going to trust Jeftichew, mostly because Charlie knows many Royals believe him to be little better than Stanley, but also because Charlie only hires Casters from the MK temporarily, and does not pop them. Charlie hires casters to perform specific tasks, and he cannot know Parson will be in the MK unless he does as described above, buying the services of a variety of disciplines, just to get to the point where he can hire anyone for the job. Additionally, while Jeftichew's oath probably carries no Natural Thinkamancy now that his Ruler is dead, it is highly unlikely he'd switch so totally to the opposite viewpoint of his former Ruler. He will always be disinclined to work for Charlie, because Royals believe that Charlie is already working with Stanley. Jeftichew, even if told of Parson by Charlie, will not switch his hatred to him, just because a Toolist tells him the guy is dangerous. And Jeftichew is a leak that might inform any Royal sides that he serves. Jeftichew has let Sizemore pass into MK unscathed, so why would he fixate on Parson, even if someone else wanted him to do so?
If Jeftichew is simply lying in wait for Wanda, that scroll is going nothing less than brutally lethal. Carnies are not non-violent. They need to deal with people that get angry for them using their cons and tricks to take people's money. While he has elements of George Harrison, he also has elements of a circus performer. He is going to con Parson, just like a Carny, but it will be Wanda that is the victim.
Oh, and BTW...
Fedor Jeftichew billed himself as "Jojo the Dog Faced Boy." The tie in to "Get Back" and the similarity between uniforms with George is remarkable, except Get Back wasn't on Sgt. Peppers with the uniform (It was on their last album, Let It Be). Had it been, I might have suggested that the name chosen for the man in Get Back came from Fedor. "Being for the Benefit of Mr. Kite" came directly from a circus poster purchased by Lennon, after all, so he did steal from that industry for his lyrics.