Richard, I can't speak to WikiTree's policies and guidelines regarding setting and documenting the "Confirmed with DNA" status, so I probably shouldn't be saying anything at all. But that's seldom been known to stop me...
The term "triangulation" was first used in conjunction with genetic genealogy in 2001 when it was was borrowed from the land-surveying practice of vectoring precise locations. It was and is clearly applicable for use with the non-recombinant Y chromosome, albeit the analysis standards have changed and become a bit more rigorous with the advent of the Big Y full-sequencing test and our improved understanding that lower level STR panels, like 37 markers, are entry-level and difficult to use with accuracy closer than several (or more) generations past.
So, in my opinion as a DNA dweeb but not as representing WikiTree, 111 Y-STR triangulation should certainly be usable.
Somewhat unfortunately, it was a decade after the yDNA triangulation concept came to be that it was adopted--conceptually almost unchanged--for use with low-resolution autosomal SNP testing. To this day, we still have no scientific, peer-reviewed research that indicates one way or the other that our popular concept of autosomal triangulation is a valid methodology among distant cousins when using autosomal DNA. That said, I personally believe it should be valid for closer relationships, and your ~25cM shared segment among three 3rd cousins would, for me, add evidentiary strength to the Y-STR triangulation. Though that would be in addition to the basic "Confirmed with DNA" citation statement or included in a more extensive discussion of DNA evidence in the body of one or more profiles.
WikiTree must--understandably--walk a very fine and tenuous line in these matters between simplicity and accuracy. Often, those objectives will be mutually exclusive. My personal opinion, and worth every cent you've paid for it, is that the "Confirmed with DNA" citation statement is a convenience for the purpose, but as it stands can almost never meet the evaluation and documentation requirements of the genealogical proof standard. Genetics, in all but instances of the closest family members, is too complex.
And, also unfortunately, privacy requirements to which WikiTree must adhere mean that we cannot construct, in the majority of instances, an evidentiary citation that is meaningful anyway. The "specific location of each piece of data" is often inaccessible by others, and the evidence analysis requirement "to record details that affect the the use or evaluation of those data" often isn't possible because, by definition, we usually have DNA testing information only on living or recently deceased individuals.
I may have misread what Mindy posted, but one of the exceptions there, I believe, are the public, group DNA projects at Family Tree DNA. If a project member has agreed, through FTDNA, to allow his Y-STR and haplogroup information to be displayed publicly, it's done so in an entirely anonymized fashion. The kit test number shown in those results can't be located in any other way or associated with a living individual, whether by name or initials or by any other means. Even if I am shown a match in my personal FTDNA dashboard, I can't see that person's kit number unless he discloses it to me directly. Only the project administrator, who has signed an NDA with FTDNA, can associate a kit number with the individual who manages the kit. And we absolutely will never reveal what kit numbers are associated with which individuals.
The FTDNA kit numbers are of use only if the test-taker has joined a group project; has granted permission for his test results to be posted anonymously; and if the project itself posts those tables of results. For yDNA citations involving tests taken at FTDNA and appearing in public FTDNA projects, I would always use the kit numbers.
