If I were the Dubai police, I would just quietly drop the investigation, it is clear that they have no leads and have no idea what happened. Mossad won this battle, maybe they can improve their security rather than chasing not knowing what they're looking for.... They are just making themselves look like a joke at this point.
Netanyahu: Most of Americans see eye to eye with Israel on dangers of Iran deal (Haaretz)
from the article: Canada denies arrest of suspect in Dubai assassination