I would love to know the real story.
My take is that he doesn't want to let Sasha go because he likes the familiarity of her; they have a laugh together, his family probably like her, they are comfortable together etc. (I would like to be wrong and he actually loves her to death, but I've let common sense win here)
I don't believe he is scared of her selling her story, or his reputation being damaged (he isn't Beckham, he doesn't have a brand to protect). I understand if he doesn't want to appear in the vlogs but for his mere existence to be essentially air-brushed out is a bit OTT for me. Not to mention completely unnecessary as we know they are together. I also don't believe he's kept Sasha around because that is what the clubs want, that's such an old fashioned attitude.
I feel for her, I think she seems lonely in the vlogs, she lit up (in the one earlier in the week) when she was talking about going back to Birmingham to see her friends. I am glad she has Skye to keep her company.
Whatever the truth is, I hope they are both happy.