EDIT: Sorry this is for a different bug... I have found the bug you are talking about and its the hack thats broken. Lots of other people are experiencing this. Sorry about that!
Hi! I’ve experienced the same problem as you. Here’s what I did to get it working after I liked my old account.
1. Link your old account and wait for the app to crash
2. After the app crashes reopen it and wait till the loading bar starts
3. When it gets near the end of the loading process, it will say “Loading scene” and at this point you will need to quickly open your control center and turn airplane mode on!
4. You will need to airplane mode on for a reasonable amount of time until you turn it off.
5. After a few times of doing this trick your game will open without crashing and you wont need to enter airplane mode anymore to start the app.
NOTE: Some progress will seem like its missing (pets/clan) but just keep playing and it should come back after a while.
Hope this helped!!