It's been noted in a 2017 article that that year only Moldovan president Dodon attended the May Victory Day parade in Moscow:
Dodon was also the only head of state from the former Soviet republics in the Commonwealth of Independent States who stood at Putin’s side for the May 9 Victory Day Parade, marking the end of World War II.
Is this unusual though? I found from a 2015 article that said that Western leaders sometimes attended in the past but were snubbing the parade that year (although Merkel visited the next day, in a lower-profile event.)
However, I could not find whether the 2017 occurrence of only the Moldovan president attending from among the leaders of former Soviet republics is actually unusual. Did e.g. pre-2014 parades see more of these former Soviet republics leaders attending the parade?