I know that after Mass, in the sacristy, a lay person who wasn’t the serving acolyte or EMHC would sometimes do the final purification with soap and hot water. I wonder if that had something to do with the indult.

Thats the only thing I could think of.
Thinking about what exactly is the difference between an EMHC, an acolyte and a duly instituted acolyte;
Wouldn’t it be possible for an EMHC to also be an acolyte even though she/he is only serving in assisting with the Eucharist?
Wouldn’t an EMHC, who was fully trained and registered with the diocese to act as an EMHC, then be considered a duly instituted acolyte for that ministry?
Maybe I am misunderstanding but according to what I am gathering from Fr. Hardon’s dictionary, an altar server is considered a duly instituted acolyte. Am I mistaken?
A couple of points to keep in mind,
No one is an “extraordinary minister of Holy Communion” That’s a point the Church has been making over and over again in recent years. I don’t say this to be critical of you, but in order to understand the rest of what I’m saying, that point has to be kept in mind.
The function of an EMHC only exists while that person is actually engaged in assisting a priest in the distribution of Communion. Once that “moment” is over, the person is no longer an EMHC. In reality, no one can ever say “I am an extraordinary minister of Holy Communion” unless that person is actually engaged in distributing Communion. There is no such office. That’s exactly what the qualifier “extraordinary” means.
Certain people are potential EMHCs. First among these are instituted Acolytes.
(The bishop can also appoint certain persons to be potential EMHCs on a stable basis, but they’re still only EMHCs when they’re actually distributing).
What we now call “acolytes” used to be “subdeacons.” They were ordained to this order. In the early 1970s Pope Paul VI discontinued the order of subdeacons (in the Latin rite) and replaced it with the ministry of Acolyte. Acolytes can only be installed by the bishop, using the proper liturgical rite (sometimes the bishop can delegate this rite to a priest). Although it is not an ordination, it can sometimes be helpful to think of it *as if *it were an ordination. Acolytes are installed, not ordained, and so are laymen, not clerics, but once installed, they remain so for the rest of their lives. In most cases, this ministry is only conferred on those preparing for the priesthood or diaconate.
The word itself “acolyte” can also be applied to other laypersons who are appointed to perform the liturgical role of an instituted Acolyte on a temporary basis. It can indeed be confusing because there is a significant difference between an “acolyte” and a “duly instituted Acolyte.” The instituted Acolyte should always perform his office whenever he is present at Mass. On the other hand a temporary acolyte may only function when there is an absence of an instituted Acolyte.
An instituted Acolyte is
de facto (ok, for the purist,
ipso jure) a potential EMHC when there is a genuine need. Again, temporary acolytes can only be appointed EMHCs when there is both a genuine need and a lack of instituted Acolytes.
What I’m trying to say is that
it is not a matter of saying that an EMHC is a potential acolyte, but it’s precisely the other way around: an acolyte is a potential EMHC.
Clear as mud now? I hope this helps.
As for your first question, the sacred vessels must be purified by a cleric or a duly instituted Acolyte, but once they have been purified, anyone might clean them in the sink. The indult had nothing to do with this “cleaning” part, only the purifying part.