I’m unsure if this is written as:
‘Worse even, than…’
‘Worse, even, than…’
‘Worse, even than…’
Or without commas at all.
I tried looking it up, but all I can find are examples of the usage of ‘worse still’ and ‘even worse than’.
Even has been inserted into the phrase worse than, so I would put a comma on each side of it.