Unit Manager asks to cancel interview. What do you do?

Recently I had my first RN interview on a Med/Surg unit at large urban hospital. After a nerve racking session of gruelling questions, the manager had suggested that they would give me an opportunity to work on their unit but wasn't able to officially hire me. He mentioned that the official hire would occur once my references were cleared with HR. I sorta interpret this as you're hired but just not yet. Happy and confused all at the same time. Does this mean things could change?

He also suggested to me that I don't go on any other interviews and solely work for their unit. Mind you the position I was hired for is casual, but working at this hospital was my top choice out of all my possible opportunities. After spending years living as a student, I am yearning to obtain some stability and security in my life. This means I am eager to work and pay off my debt.

Later on this month I have 1 more interview set at a busy acute medicine unit at another large urban hospital. I have spent many many months working here as a student. I know the unit like the back of my hand. This appeals to me because I know I would do a good job there. The downside of working here is the likelihood of burning out fast. The assignments are tough and there is a lack of staff to assist you. But I would learn to be a ninja nurse and it would facilitate other opportunities.

Even though I feel that I will most likely get hired, I fear that things may change and I am left without a job. By cancelling my interview, I am ultimately placing all my trust with 1 organization. Unsure what to do yet, I have not cancelled anything. I really appreciate your input or hear your experiences. Thank you again for taking the time to read my post.