The original priority date was in 1994 US5662332 so my assumption was that it had expired, but upon searching Public Pair using the application number (US 08/544,306) it comes up that it's under Re-Issue and still patented. So my question is, is the patent actually expired or does the re-issue extend the term somehow, or is there something else that's extending the term beyond the 20 year window that I'm missing? Thank you for your time.
You need to calculate expiry from the US5662332 Re-issue is just publication of information. Here is another answer to calculate the same How do you determine a patent's expiration date?
MPEP 1405 Reissue and Patent Term [R-11.2013]
35 U.S.C. 251 prescribes
the effect of reissue on the patent term by stating that "the Director shall… reissue the patent… for the unexpired term of the original patent."
The maximum term of the original patent is fixed at the time the patent is granted. While the term may be subsequently shortened, e.g., through the filing of a terminal disclaimer, it cannot be extended through the filing of a reissue. Accordingly, a deletion in a reissue application of an earlier-obtained benefit claim under 35 U.S.C. 120 will not operate to lengthen the term of the patent to be reissued.