CNCPro,
Does your model actually have this v-shaped trough drawn in accurately? Are the cuts long straight sections?
Can you simulate this tool with a very small radius ball mill? You could calculate the radius of ball that will fit within the section of your V tool. Depending on the actual proximity of steep vertical walls, you might be able to fudge it with a small diameter Vpoint replacing the tiny ball tool.
In any case, you aren't going to want to go over the entire model with a tiny point because the amount of stepover is going to be extremely small. Perhaps you can create a clever contoured boundary above the intended "v-path" to constrain the tool to very directed cutting, without allowing it then to stray over into other finished surfaces. This would be like a parallel "guide track boundary" equal to the tool width of the body of your V tool.
Theoretically
(see below)