I barely knew R. Poliakoff - met him maybe once or twice. He was a friend of my grandfather, who was a rav in Baltimore for much of the same period and who was about the same age. I crossed paths with several of his children and grandchildren over the years - I tutored one of his grandchildren and was tutored by another of them.
He was known as a classic Lithuanian independent thinker, as evidenced by his book Minhagei Lita, reviewed here and here, and by his position on using a microphone on Shabbat (perhaps the RCA will allow for temporary circumvention of their pay-wall). Though both exhibit independence, the former example is a diatribe against the contemporary yeshivishe world, which he claims has deviated far from the Lithuanian Torah world that it claims to imitate, and the latter is an exercise in real lomdus.
For many years, Baltimore has been blessed with interesting and fascinating rabbanim and talmidei chakhamim who seem to slip under the radar. Rabbi Poliakoff and R. Mendel Feldman, who I wrote about a few years ago, belonged to one generation of such rabbis, but their ranks are in no way depleted (ve-hamaskil yidom). I was gratified to see that R. Ezra Schwartz recently cited from the Torah of R. Michoel Forshlager, perhaps the greatest of Baltimore's unknown giants (a recent article about him is here, though I seem to recall that R. Dovid Katz wrote an earlier article, which I can't seem to find).
Here's a picture (from this archive) of R. Poliakoff as a US Army chaplain in France in 1945. I believe he's the once standing directly behind the young boy: