Either there really is some discord behind the scenes of Human Centipede 3 and Tom Six is leveraging an upcoming lawsuit against the actor Dieter Laser for all the publicity he can, or Laser is just a better liar than the Six family because he's issued his own statement on the situation and it seems all too plausible.
Here are Laser's words, as sent to the super German webzine, Screen/Read:
It's very simple: I loved the story when it was told, got the contract and the promise to have the script in 4 to 6 weeks.
When it arrived – half a year later and only after the official announcement – I didn't like the realization at all, couldn't identify with the character the way it was written and developed immediately and enthusiastically in a day and night marathon a version full of concrete and practical suggestions which would enable me to play the lead full throttle – same procedure as with Dr. Heiter – but this time it also would have had some unavoidable effects to the dramatic structure.
That was too much for Tom and since he couldn't live with my suggestions and I as a method actor couldn't identify with his version, I told him that I couldn't see any other way than that he would have to 'change horses'. That's it.
That second paragraph was a single sentence. Crikey.
So it seems that Tom Six may well indeed need to go back to the whiteboard.