It may be more difficult to answer than you think once the lawyers get involved
91.113 Right-of-Way rules:
(g) Landing. Aircraft, while on final approach to land or while landing, have the right-of-way over other aircraft in flight or operating on the surface, except that they shall not take advantage of this rule to force an aircraft off the runway surface which has already landed and is attempting to make way for an aircraft on final approach. When two or more aircraft are approaching an airport for the purpose of landing, the aircraft at the lower altitude has the right-of-way, but it shall not take advantage of this rule to cut in front of another which is on final approach to land or to overtake that aircraft.
So if the R-44 was "approaching an airport for the purpose of landing" then he had ROW because he was at the lower altitude, but if he was "operating on the surface" the Bonanza had the ROW. If the R-44 was "attempting to make way" then the Bonanza may be at fault, which is how I tentatively see it. But how do you actually "force an aircraft off the runway"? Either way it sure loused up a nice day for flying for both of them.
I wonder how the FAA is going to sort this out. It'll be interesting to read the NTSB report (next year
).