Thanks for sharing what resolved the issue. In case that’s unclear to anyone, see the resolution:
One doesn’t have to recreate the database when migrating to a service. One can move it instead.
One can also recreate the database without migrating, and it might be a simpler experiment to try.
But there are a number of experiments suggested, and it would be good to gain an understanding.
One possible way to get both might be to time the Verify files, move database aside, Repair,
then time the Verify files again. Checking Profiling log for SQL execution times may also help.
A recreated database will likely be smaller than even the original after vacuum, because it will lose
some history such as the job logs and remote operations done. log-retention keeps them trimmed,
and I can’t think of any data-oriented tables that grow to the sky. Still, it might be fast after recreate.