As far as I know, the financial troubles started and ended with Boothby. The speedway itself was always solvent, only impacted by Boothby taking many out of the club. He's no longer involved, with Courtney, Austin and Timmo now at the helm. The speedway side of the business makes money, attracts good crowds and could afford it.... the big IF is how much is now being paid to the stadium owners to be able to operate (without the greyhounds to pay a cut).
The Oxford Stadium website seems to suggest positive movements though, posting about a 'new era'... https://oxford-stadium.co.uk/