A fundamental flaw.
I don't think so. This particular question is constructed so you don't need to know the track.
From the question details, specifically the starboard drift, we know the heading is 4 degrees left of track.
Separately, we are told that the NDB is 90 degrees left of track.
RBI measures the Relative Bearing, ie the difference between NDB direction and Heading. Both are stated as offsets to a track, so the actual track is irrelevant.
For the mathematicians:
RBI = (Track+270) - (Track-4) = 274.
I also dug out my 2006 5th edition of the IMC Confuser which has a similar question, but a different conclusion.
Q31: When maintaining a mag track 330, you experience 8 degs of starboard drift. What will the RBI show when passing to the left of an NDB when it is exactly at right angles to the track? A=074, B=090, C=082, D=098
The correct answer is D, according to the book.
Applying my "track free" method:
With no wind, and the NDB at right angles to the right this time, the RBI shows 090. With 8 degs of starboard drift we have rotated the aircraft 8 degs to the left, so the RBI shows 098.
Which matches the answer in the 2006 Confuser, and we didn't need to know the track, because of the way this particular question type is constructed.