I am happy to answer any questions specific to IB.
Unfortunately you would not be a suitable candidate to be sponsored by an IB unless you have a specific skill that couldn’t be sourced locally. This will make it very tough to remain in the US post undergraduate on a visa for an IB.
IBs typically will not post on their websites regarding such issues as it is a matter of immigration law not company policy or preference.
You were specifically directed to a BNP summer internship. Please be aware that just because a bank is a global bank and interviews on campus, it doesn’t mean that it hires internationals for US employment.