There’s a lot that is unknown about this situation; how long this camshaft has been in there, was it there the last time the inspection was due, the camshaft profile, details about the valve lifters/lash, and the state you live in are some of those unknowns.
With a performance problem one should always check the compression first to weed out any possibility of a mechanical fault. (say an inadvertently bent valve due to a broken timing belt, a timing belt that not installed correctly after a cam change, etc.)
With some camshafts the engine may not pass emissions anyway, misfire or not.