Leaving money in the account is not a tax issue ... needing to pay income tax on the earnings is the issue. Depending on the amount it earns you may need to file a 1040NR. TurboTax doesn't support that form ...
https://blog.turbotax.intuit.com/turbotax-news/turbotax-and-sprintax-now-make-filing-easier-for-non-...
https://www.sprintax.com/non-resident-alien-tax-1040nr-turbotax.html
