Does the Eastern Orthodox have an infallible canon list?

For Eastern Orthodox Christianity, the canon of the Holy Bible is authoritatively listed by the Canons of the Orthodox Church.

It is fundamentally important to recognize that the establishment of these approved lists of acceptable scriptures predominantly originated with individual bishops and regional synods, who endeavored to counteract the proliferation of heretical writings.

It is equally critical to acknowledge that not all regionally formulated lists received endorsement from an ecumenical council. (This is noted in the question as well)

Additionally for us the inclusion or exclusion of a text within the biblical canon is not determined solely by manuscript evidence.

I know that the Quinisext Council may be seen as an emendation of the decisions of the fifth and sixth ecumenical councils, but is it therefore regarded as infallible despite not being itself an ecumenical council?

The Eastern Orthodox Church grants it significant authority treating it as an extension of the Sixth Ecumenical Council. Its canons are included in the Orthodox Church’s canonical collections and are considered binding.

This Council is basically the 6th Ecumenical council part 2.

According to the author Romanus in his Prolegomena to the present Council, the prelates who convoked the Sixth Ecumenical Council in the reign of Pogonatus convoked also this one in the reign of his son Justinian.

Also the Seventh Ecumenical Council, welcomes and embraces the canons from this council all the way to those of the Apostles.

we welcome and embrace the divine Canons, and we corroborate the entire and rigid fiat of them that have been set forth by the renowned Apostles, who were and are trumpets of the Spirit, and those both of the six holy Ecumenical Councils and of the ones assembled regionally for the purpose of setting forth such edicts, and of those of our holy Fathers. For all those men, having been guided by the light dawning out of the same Spirit, prescribed rules that are to our best interest. Accordingly, we too anathematize whomsoever they consign to anathema; and we too depose whomsoever they consign to deposition; and we too excommunicate whomsoever they consign to excommunication; and we likewise subject to a penance anyone whom they make liable to a penance. (7th Council, Canon I)

Despite not being defined by any of the seven ecumenical councils, does the Eastern Orthodox Church have a belief in an infallible canon list for Scripture? If so, how is it known to be infallible?

Well at this point the first half of the question has fallen apart, we believe that the 6th Council did exactly that. (And as such would be "infallible")

Additionally it has been "reconfirmed" multiple times. From the 7th council onwards in every council that reaffirms the previous canons. So the 7th Council technically also "infallibly reconfirmed it"

Related extra information.

This is technically beyond the question, but I felt like sharing?

There are several sources for the Canon specifically named, not just the 2 you mentioned in the question. They are listed in Canon II of the Holy and Ecumenical Sixth Council. However I think a chart is easier to read so... here you go.

Here is each of those side by side.

1. St. Amphilochios that "As for the Book of Revelation of John again, Some approve it, but at least a majority call it spurious." Yet note that this statement is followed by “This should be a most truthful canon of the God-inspired Scriptures,” suggesting that he accepts the book. It might also be noted that St. Gregory eventually came to think of the Apocalypse with some regard, for "in the constituent address which he made to the one hundred and fifty bishops composing the Second Ecumenical Council he expressly mentioned it, saying 'For I am persuaded that other ones (i.e., angels) supervise other churches, as John teaches me in Revelation.'" (Hieromonk Agaptios and Monk Nicodemos, The Rudder, p. 153)

Hope the extra stuff was interesting.