The presence of three individuals at the limit of the Golden Core Stage is indeed a cause for concern.
After all, to obliterate a Sect with three such experts requires a significant cost. Of course, he has no doubt they can destroy the opponent's Sect. Even if they are gravely weakened, his Heaven Prayers Sect is still a Great Teaching; it's just a matter of how steep the price is.
However, while they can destroy the opponent's Sect, they are unable to kill the three at the limit of the Golden Core Stage.
If there was only one at the limit of the Golden Core Stage, they might have a chance to intercept and kill that person.
But with three at the limit of the Golden Core Stage, unless these three stoutly defend their Sect, if they all intend to escape together, then it's simply impossible to stop them.
By then, if their Sect is exterminated by his Heaven Prayers Sect and they are single-minded in seeking revenge against the Heaven Prayers Sect, that would be a serious problem.
