Yes, I have the exact same problem in Penny's Pursuit since the latest 12.3.1 game update. Same device/OS as yours, iPad 5th gen running iPadOS 16.7.11 (20H360), which is still supported.
Before this latest PvZ2 update, I got only occasional crashes (maybe 15%-20% occurrence rate) when reaching the reward page after beating Zomboss in Penny's Pursuit. But after this latest PvZ2 update, I get those crashes almost all the time (over 95% occurrence rate).
Note that if the crash occurs when you press the Skip button (or when you progress through the reward animations), you do get the reward and then after you've restarted the app you see the green checkmark for beating Zomboss. This is what happens most of the times. But sometimes the crash occurs right before the Skip button is even shown, so you only get the gold base reward and then after you've restarted the app you see the red X for losing to Zomboss.