The 2 standard ways I normally use when I do stupid things is either to use the recyclebin (ou=recycleBin,ou=itim,<your org>) or use a recent ldif backup - locate the old working version and replace the workflow again under ou=operations,ou=itim,<your org>....
My standard recommendation is always to do at least daily ldif backups and keep 1-3 months of these available.
Recyclebin is not enabled by default I believe so that option has to be enabled to use recyclebin method...
My personal preferred tooling is to all ldap manipulation using Apache Directory Studio as it allows you to manipulate binary attributes very well...
HTH
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Franz Wolfhagen
WW IAM Consulting Leader - Certified Consulting IT Specialist
IBM Security Expert Labs
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