The Russian Orthodox Church is not affiliated with the Pope. Here is the list of Churches that are:
en.m.wikipedia.org/wiki/List_of_Catholic_rites_and_churches
Catholics can only receive the Eucharist at Churches who follow the Pope. As to venerating a sacred relic, I think it would be best not to.
Sorry to say this, but what you are saying is in direct discordace with the Magisterium of the Roman Catholic Church. Both the CIC/1983 and the oriental codex, as well as at least one papal declaration or encyclic state quite clearly that not only is receiving Eucharist and penance from the hands of Orthodox clergy not invalid or sinful for Roman Catholics, but more, it is, under the ennumerated conditions, even “licite” (as in, not “illicit”).
Honestly, and I am not reprimanding anyone, God forbid, especially not anyone who is out of my jurisdiction, but I always thought it was not all that, how to say it, “wise”, to say publicly things that are in discordance with the Magisterium. One should be careful there.
Please do not be angry with me, an Eastern Orthodox bishop, for pointing this bad habit out, but I have met it far too often and far too much, that Roman Catholics said things like these. In no way does my post mean to infer that I consider such bad habits or wrong practice a representation of all Catholicism or eve of all Roman Catholicism. I just state I have met this a lot. Like, really, a lot.
And a practical matter: even if we (Orthodox clergy) are not bound by the Roman Catholic Magisterium, those of us who have a loving heart do offer Eucharist, Unction and Penance to Roman and Eastern Catholics (if certain conditions are met). We do not have your Magisterium (sometimes I ponder it might not be so bad to have an office like that…), but we can do this even though. One day all priests and bishops, Eastern and Western alike, will stand before the Throne of our Father in Heaven and He will ask each one of us why we refused His mercy in form of Eucharist or Penance or Unction to His child here and here and here. What will we say? Do not get me wrong, you cannot serve these Holy Mysteries to everyone who walks through the door, that would be very bad, but I see too often such… dead letter and red tape over life and mercy. Personally, I met more cases where the terms and conditions could, with a little help and good will, be met so the Holy Mystery could be served, than those where it was truly impossible.
And if I was ever, in a case or two, perhaps too trusting and too generous with the Holy Mysteries, with my head bowed down I ask my beloved Father in Heaven to forgive me, I only did it from the love in my heart, one which I know He put in there, not me.
However here reads this and will not disdain a blessing from an Orthodox bishop, please have it: Oh the Most Pure Lady Theotokos, who art the shining light leading us to your beloved son and our beloved master, please bless these souls here with your neverending intercession, patience and peace. Amin.
In Christ,
+Gavrilo, Bishop of Czechia, Synodal Exarchy of Vlahia
Greek Orthodox Church, Metropolitan Synod of Avlona (under omophor of His Beatitude Angelos)