Re-enter US on VWP from Canada after J1 expired as UK citizen [closed]

I am about to finish my internship under the J1 visa, but I would like to spend the summer travelling through the U.S for longer than the grace period of 30 days would allow me to. I have family who are Canadian citizens and was intending on flying up to Vancouver for a weekend when my grace period is over and then re-enter under the VWP. I know that ESTA does not guarantee me entry and it is eventually at the discretion of the IO at the POI, but I wanted to ask whether anyone has actually done this in the past and whether it worked or whether they got turned away.

All I could find online was a lot of assumptions and conflicting advice, but no actual experiences, so I would be grateful if someone could share if they have attempted this.

I will have a return ticket and I have a confirmed and accepted place for further study in my home country starting within a week after I intend to leave the US. I am also not returning to the city I had my J1 placement in, but a different one. I also have proof of sufficient funds and by the point of re-entry would have a travel itinerary with hotel bookings.

Thanks