I'm going to go against the grain. I think she'll come back and start off with some healthy (by her standards) mukbangs. They'll be shit she makes herself and struggles even getting through because she's enjoying zero of it. Off screen, she'll hit up the fast food, which she has been doing already, but hide it from her viewers because she's terrified of any criticism. Eventually, she'll introduce some type of takeout, probably a foreign dish, that she'll claim is pretty healthy, but clearly not, and then eventually tell the viewers that she isn't diabetic at all and it was just a false reading but she will still continue to eat as healthy as possible. This will eventually turn into a pizza mukbang from Pizza Pizza where she lies about it being ages since she last had their pizza and that she needs to treat herself sometimes or she won't be able to sustain since if she gets restrictive, she fails, you know?
What's really fascinating with Chantal these past two years is just how short her commitment to eating healthy is, even if, before, it was all a lie and she was eating off camera. Chantal could at least hide from most her viewers for a long enough period that it appeared she was actually changing herself. She'd even get up into the weeks, not days, of her changed habits before eventually crashing and admitting it was a lie and she had been eating off camera all this time.
She hasn't done that for a minute now. All her fad changes last only days instead of weeks and she begins the new process of the cycle. So, I'm going with the idea old Chantal makes a brief appearance and we get this song and dance from her for a week or two, maybe even three (especially if she can get away with doing limited uploads) before it becomes very apparent nothing has changed.
I still believe she'll announce she's not really diabetic because putting that level of restriction on her actions is not going to cut it for her. She can't handle that level of hate if she were to continue eating horribly. She is not as thick skinned as Hungry Fat Chick, who's pretty much lost any level of sympathy from her watchers and now has tons and tons of comments from people telling her to seek help. Chantal will still get hate but she feeds off those positive comments and as long as she can use them for sympathy, she'll do it. But that sympathy has always waned the more she refuses to change and it's likely why she's become more and more manic the past couple years.
So, we'll see. I think she's dying for ass-pats and will milk this until she can't and that means secretly eat off camera, lie on camera, and do just about everything she can to avoid weighing in. Then, when she realizes the ass-pat focused videos don't bring in the audience as much as her freakshow eating does, she'll give up the charade.