Well, I guess you would have to ask yourself which outcome is more probable:
1) Moore really won the election, but the vote totals were off by 670,000 votes by mistake or fraud in Jones' favor.
or
2) Roy Moore wasn't a likeable candidate.
Where are you getting 670,000 votes? This election was swung by about 21,000 votes - and that’s not yet counting the military absentee ballots. How many fraudulent votes can there be? Well.... Jill Stein gave up on finding it out when she realized they were finding a LOT of fraudulent votes that all seemed to go for Hillary...
We have screenshots of Reddit asking out-of-state dems to go to AL and vote. We have video of an elated out-of-stater saying they had come from all over the country to vote for Jones and had gotten him elected.
The democrat counties reported after a long delay and a former official from that area has said there is always fraud there.
According to https://bigleaguepolitics.com/evidence-voter-fraud-alabama-mobile-county-results-come-late/ , glitches were reported in Madison and Jefferson Counties, with a lot of people having to file provisional ballots which I believe have not been counted. DHS had warned about “Russian” (ha!) hacking attempts on AL’s voting database, saying that the big danger is that somebody could hack the system and disqualify voters. If that was the case, those people would file provisional ballots, as happened in Madison, and Jones beat Moore by about 20,000 votes in Madison County.