INVALID_FLD_VALUE on taxcode when trying to transform an opportunity into an estimate.

I've tried various combinations of setSublistValue and setSublistText with the internal id and/or name of the tax code, but everything I try either returns an INVALID_FLD_VALUE error or INVALID_KEY_OR_REF error. The code below returns a INVALID_FLD_VALUE error. I've talked to other people in my company and there shouldn't be anything wrong with how we have netsuite configured. However, I am successfully able to do this in the UI which would mean I must be doing something wrong in my code. Any input would be greatly appreciated! Feel free to let me know if more details are needed.