I went through the trouble of correcting the spelling of the words "beherit" and "Qliphoth" in your post.
Anyway, the Skull Knight did not eat a beherit when Guts faced off against Slan in volume 26. He used his beherit sword technique (covering his sword with the melted beherits he had been swallowing over the years) to destroy the Qliphoth.
So Guts does indeed still carry a beherit, the one he obtained from Vargas in volume 2. The reason he has been carrying it was so he could find a way to summon the God Hand, his goal being to strike them down, obviously. But as Flora explained to him, that's just not how it works. Since then, it's mostly been Puck who has held on to it.
As for the idea that Guts would use the beherit to become an apostle, it's obviously nonsensical. There's a dozen reason why it won't happen (which we have gone over many many times in previous threads on the subject), but you already pointed out what matters: it would be completely contradictory to his character. Honestly, anyone even entertaining that idea is merely broadcasting to the world that they don't understand the story.