He couldn't even replicate them on said album tours lol. Like he said, he had no technique at all until around Colony, he just screamed. And you can hear it clearly. He could as you said, not replicate it, neither then or today.
And Yagami listen to this live version of Resin from 1999, he's saying ''each day I crawl to the HEART of the SILENCE/SILENT, no question about it. Sounds mostly like he says silent. You can hear the ''art'' ending clearly, then you can hear him start the word with ''SILE'' clearly as well. And that's right after the album was written so I think it's most likely the lyrics are correct there. I have though, heard him say giants on 1 or 2 performances in one of the choruses like 6-7 years back, but that's probably because he just looked up the lyrics (I doubt he has the original lyric papers lying around) in the booklet or online. In the new krakow clip he says ''Hall and halls of the giant'', but it's like I said, because he's looked the lyrics up. Makes no sense why he would clearly say silence on the album and even say ''heart'' instead of ''hall'' on the 1999 show. There are other examples on the old albums where he says different stuff than the actual lyrics as well, can't be arsed to dig up the small parts of whatever songs that is though.
https://www.youtube.com/watch?v=Wxewa8toJ6Q