Exactly this. (and for those unfamiliar with the terms, in federal courts "Circuit Courts" are the first level of appeals courts, which both sides have a right to be heard in, followed by the Supreme Court which is discretionary and only takes on big cases)

When there is a "circuit split" like this, with different appellate courts going in opposite directions you are almost 100% guaranteed SCOTUS has to step in to fix it.

I don't know the outcome of this, as I've not studied border searches in years, but while SCOTUS went in the favor of defendants on prior search cases (e.g. Riley v. California, 573 U.S. 373, cellphone searches on person during arrest; Carpenter v. United States, 585 U.S. ___ (2018), cellphone GPS logs from carrier; United States v. Jones, 565 U.S. 400 (2012), GPS attached to car), the court has changed to the right, which generally (but not always) means less defendant-friendly, more government-friendly.

If I had to wager, SCOTUS will uphold warrantless border searches.