Do you have a reference or link?
My apologies, I could not find one with the UHoJ acknowledging indoctrination as valid. I seem to have misremembered.
But the Universal House of Justice if it opposes indoctrination only does so for marketing reasons.
Consider this Baha'i website;
Does Religion Help or Hamper Children Spiritually?
It starts out referencing the recovering Catholic/Jew, one of whom claims to be recovering from, "“A lifetime of indoctrination, which made it hard for me to think for myself.”
It then references the 19th century philosopher Arthur Schopenhauer who summarized the basic concept of indoctrination;
'If, in early childhood, certain fundamental views and doctrines are paraded with unusual solemnity, and an air of the greatest earnestness never before visible in anything else; if, at the same time, the possibility of a doubt about them be completely passed over, or touched upon only to indicate that doubt is the first step to eternal perdition, the resulting impression will be so deep that, as a rule, that is, in almost every case, doubt about them will be almost as impossible as doubt about one’s own existence. –
On Religion: A Dialogue'
It then begins to explain that for Baha'is it is not to do indoctrination, but rather, "While the children are yet in their infancy feed them from the breast of heavenly grace" and goes on to explain that this includes, "Schools must first train the children in the principles of religion, so that the Promise and the Threat recorded in the Books of God may prevent them from the things forbidden and adorn them with the mantle of the commandments"
The irony of saying we should do this but not indoctrinate them seems to be lost on the author of the article.
Teaching children that the principles of religion are true and that the promise and threat of God are true sure sounds like indoctrination to me.
In my opinion.