Can one "cut a deal" with the IRS without it ending up in legislation (i.e. tax law)?
Legally no, but in practice the president has been trying to assert the power to unilaterally levy taxes, even in spite of the supreme court ruling that you need the legislature to pass a tax. People still paid the tariffs. I would be extremely suprised if that's the only place this admin is trying to tax by fiat, and tax policy enforcemetn is far less visible than consumer tariffs.
Not without a big beautiful bribe [1] I assume
[1] https://www.theverge.com/news/737757/apple-president-donald-...