The function does the calculation based on the clipping Frustum(Whatever the hell that word is).

So yes, you should be able to line it up, by adjusting the draw vec by the offset of the view-panel size. Figure out the xy difference ex 25%x25% then you can vec_scale or vec_normalize(draw_vec,0.75); before the call to draw_text

Edit - The above would only work if you target bmap is anchored at pos [0,0]. Otherwise it will take more to adjust the text.
Basically I would assume the engine sets VIEW pos [0,0] x VEIW size. So to adjust you have to offset by the difference of targetmap pos and size.