Evaluating the components of the prediction:

1. “51–49 in favor of Biden right now”
   This is framed as a slight probabilistic edge, not a guarantee. Joe Biden did, in fact, ultimately win the 2020 U.S. presidential election, so viewing him as a narrow favorite on election night was directionally correct given the outcome. Major networks and the AP projected Biden the winner on November 7, 2020, after calling Pennsylvania for him. (adweek.com)

2. “We probably have at least three more days”
   Election Day was Tuesday, November 3, 2020, and major outlets did not project a winner until Saturday, November 7—four days later—matching the forecast that it would take at least about three more days to resolve publicly. (adweek.com)

3. “Maybe a bunch of court cases” / “probably … multiple court cases” (normalized)
   After the election, Trump’s campaign and Republican allies filed dozens of lawsuits—over 60 by many counts, and over 80 by some tallies—challenging various aspects of the results in multiple states. (en.wikipedia.org) This clearly satisfies the prediction of “a bunch” / multiple court cases.

4. “We may not know who the winner is till December”
   This was explicitly framed as a possibility (“may not know”), not a confident forecast. In reality, major news organizations called the race for Biden on November 7, 2020, and he was widely treated as president‑elect from that point onward; the winner was not genuinely in doubt into December, even though formal processes (state certifications, Electoral College vote on December 14) continued. (adweek.com) This tail‑risk scenario did not occur, but it was couched as a contingent possibility rather than a mainline prediction.

5. “This may require another Supreme Court case”
   Again framed as “may.” There were indeed election‑related cases and motions at the U.S. Supreme Court, notably Texas v. Pennsylvania, filed December 8, 2020, which sought to invalidate Biden’s wins in several states; the Court dismissed it on December 11, 2020. (en.wikipedia.org) While the Court did not ultimately resolve the election in the way Bush v. Gore did in 2000, the prediction that the post‑election fight might reach the Supreme Court was borne out (even if the Court’s role proved limited and non‑decisive).

Overall assessment
The concrete, time‑bound parts of the forecast—Biden as a slight favorite, a resolution taking at least about three more days, and the emergence of numerous post‑election court cases (including at the Supreme Court level)—all aligned with what actually happened. The more dramatic scenarios (winner unknown until December, election requiring Supreme Court resolution) were described as possibilities, not firm predictions, and the Supreme Court did in fact become involved, albeit without changing the outcome.

Given that the central, non‑hedged components were accurate and the rest were framed as contingent risks, the overall prediction is best characterized as “right” rather than wrong or inconclusive.