[trhway]

> I am only lead on the project, I don't manage people.

responsibility without power

>My boss trusts my judgement

looks like classic "delegation", ie. the boss delegated responsibility while kept the power (you only fall for such "delegation" the first 5-10 years in the industry).

One can guess who is going to get ultimately blame assigned :)

>Is there a possible solution to this without adversely affecting the project?

With only 2 people it is actually much simpler to do their job for them. Just send them on a long trip - like some very important future architectural R&D without any need to commit anything in the near term. Doing very important architectural thing they also may get promoted so you wouldn't have to deal with their code :) Best course of action though - just leave this project or this company.