Not exactly. It shows what a crawler saved on a given date, and some elements such as images or comments may be missing or captured on different dates.
Search for the address in news databases, other articles or old social posts, and record the addresses and dates you checked so the negative result has a clear scope.
Yes. Save the full capture address with its timestamp and keep a local copy with your access date, since captures can later be removed.
Consider why it was removed first. Pages may have been taken down to protect privacy or correct errors, so quote only what your account genuinely needs.
Cite the original publisher, title and address, then the archive, the capture date and the full capture address you viewed.