Yeah apparently the domain was used by some russian crypto scam in 2018 so its blocked by a ton of stuff. I've tried to get it cleaned but eventhough many vendors took it off their lists, others just ignore any requests.
I'm not 100% sure how federation works, I added lemmy.one to the monero.house instance but i think you might also need to add monero.house to your federation list for us to see comments?