Start here, in order to figure out if there is some chance:
‘All My Brave Tabs Gone Mobile IOS - #2 by 289wk’
And there, read the other replies. Basically, if you have been backing up the iOS device, there is some chance.
Otherwise, iOS crash reporting is unique - not like the Crash ID reporting by other Brave Browser applications. See:
‘Helpful Info & FAQ for Brave Users - #44 by Saoiray’
IMPORTANT: You would be sending the Brave Browser (iOS) crash report information that you gathered, to e-mail address: user-support@brave.com
Next, you would make a new reply - here at your Original Post - and using as a guide, what I did - in order to notify Brave Support of exactly what you have sent to them, so they can “connect the dots”: