Loading the content for the revision 5422832 (deleted, ar_id = 16629546) is not possible right now. It looks like the text table entry for that revision has never been altered after the move to external storage:
mysql:wikiadmin@db1070 [dewiki]> SELECT * FROM text WHERE old_id = 5422832;
+---------+------------------------------------------------------------------------------------------------------------+-----------+
| old_id | old_text | old_flags |
+---------+------------------------------------------------------------------------------------------------------------+-----------+
| 5422832 | O:15:"historyblobstub":2:{s:6:"mOldId";s:7:"5421409";s:5:"mHash";s:32:"1be8bf19b501233136d6e7b97e7169cd";} | object |
+---------+------------------------------------------------------------------------------------------------------------+-----------+I didn't look into this much, but I guess this needs a bit of manual poking (to find the historyblob on external storage and then to update the text table).