Yes. Clearly there was no evidence of fraud, from which one might infer there was no fraud. One can rarely speak in such absolutes.
But your basis for characterizing the election as insecure, not only insecure but the most such in recent history, is unclear.
Assuming no substantial changes are made to the system as it stands, and Trump or an ideological fellow-traveller prevails, will you regard that as potentially fraudulent as well?