I just need to know if this is possible.
Let's say I have 100k links verified on a project. But in time some of them die and I'd like to resubmit on those sites.
How would you do that or does GSA have something already built that can achieve that?
Global Options -> Advanced -> Tools -> Clean-up is what you need I think.
you may be able to post again to those failed verified links. because some of them are removed by administrators or their spam detection service.
Also, deleting URLs from verified links won't make any changes to Project's cache and history as far as I know.
Best of luck