If this person is an alumni, and they're hiring for a sales role, then I'm not sure why you think you are only following up about the job itself.
A better bet would be to follow up and ask for a coffee to discuss the industry as a whole and how you might fit into it, and general advice.
People love giving advice and their thoughts on the industry, and they like it when people are interested in their thoughts and advice. Also, as this person is a sales manager they are definitely looking for people they can get along with to hire - sales people can be pretty insufferable sometimes for their managers!
You perhaps should not be thinking about talking to this person about a job, but about the overall picture. This will show them you're not just interested in money, but actually interested in the industry. Which is more helpful for securing a role, believe it or not.
So, to answer your question - why not make this person your mentor? Even if you're not a right fit for this company, they will know people in other companies (they are in sales) which will be helpful.
I would suggest asking them for a coffee to talk, and if you and this person get along, schedule a coffee chat each month.