News outlet are being extremely vague about Orban's motives, but it's clear that no funds have been unfrozen. By the looks of it, it seems Hungary received no grants at all and just changed its mind out of the goodness of her heart, which is weird.

From DW

"From what we are hearing from our sources, they made it very clear to Viktor Orban that he is standing all alone in the EU, blocking this essential aid for Ukraine," she said, adding that following the message it became clear Orban would finally say yes and so the EU leaders sat together to finalize the deal.

This makes me wonder if anything went on behind those closed doors. We know that yesterday Orban met with Meloni, who according to euronews

[Meloni] has fashioned herself as the most dexterous mediator between Budapest and Brussels. Meloni and Orbán held bilateral talks on Wednesday evening in anticipation of the high-stakes meeting.

All that's left to hope is that Meloni and other EU leaders succesfully managed to scare off Hungary and that no backroom deals went on.