Kudos to Terry's advice: Get prudent legal advice.

Scenario 1.  All those facts were "my client told me" and you hadn't read the legal document, be aware that people tell people things that aren't exactly true or the whole truth.  Remember the game in high school that you passed down a statement and after 20, 30 participants, the statement would be all twisted?

Scenario 2.  You read the document and still had no clue what exactly to do and needed to ask for opinion here,: You need to talk to the client's lawyer.

Scenario 3.  You talked to the client's lawyer and still don't know which direction to go: Suggest to client to change lawyer.

Quite a few pieces of info are missing here.  The tax treatment has to be based on the legal treatment of the document in its entirety.   I prepare taxes.  I don't interpret the law outside the arena of tax law.

Then, as a practical matter, do you want to tangle yourself up in case the GF and Client get into a legal battle?