I have the same Boxer-Version running on an Pixel 3 XL with Android 10 in Work Profile. No crashes here. However I have multiple Mailboxes configured, being an Exchange 16 onprem the one that´s getting pushed via Console I have added two more mailboxes manually that are O365-Hosted and those are only getting pulled by forcing manually syncing and then getting the device being blocked for 16-20 minutes with no push-notifications working recently. It worked all as intended back in August.
Unfortunately due to the number of changes I can`t say if this is an Android 10 or an Boxer-Update issue.
I would recommend opening a ticket on your issue Moses. Try to retrieve Boxer-Logs and Device-Logs from the console or directly from a device, that might help getting a clue what is going on.