This is from the Australian Parliament web site:
Twelve countries are involved in the TPP negotiations but most market access issues are negotiated at a bilateral level—that is, country to country.
And here are some specifics from a CRS report:
Negotiating the terms of agricultural trade liberalization within the context of what trade negotiators have billed as a high-standard trade agreement for the 21st century continues to be central to efforts to fashion an overall TPP agreement. Within this process, bilateral negotiations between the United States and Japan that seek to come to terms on market access for a handful of key agricultural commodities that Japan considers to be sensitive and in need of continued import protection has become an important objective for U.S. agricultural interests.
If the bilateral aspects of the TPP negotiations are emphasized, is there any chance the Trump administration would come around?