In the page for "How Can I Keep from Singing", in the "Worship Notes" section (https://hymnary.org/text/my_life_flows_on_in_endless_song#worship-ideas), it cites the lyricist as Robert Lowry. I don't think this is consistent with the most recent research.
Subject: RE: song history - How Can I Keep From Singing
From: GUEST,Katie White
Date: 07 Jul 05 - 01:20 PM
... I have an original edition of a book written in 1888, Baptist Hymn Writters and Their Hymns by Henry S. Burrage, D. D. written while Lowry was still alive. ... the following quote from the book is of interest to this discussion.
"Besides his own hymns Dr. Lowry has given vitality and popularity to many productions of other writers by the music with which they are sung, such as . . . 'How Can I Keep From Singing,' . . . and a host of others."
From this, it appears that in the 1880s Lowry was known to not be the original source of the words to this hymn, but was being credited for making it known and available. This doesn't solve the debate, but I don't doubt the information for these reasons: 1) the early date of this book, written by a Baptist and about Baptists, while Lowry was serving a Baptist Church and having been a professor at a Baptist School. 2) If the Baptists wanted to lay claim to what it lists as a popular hymn, they would have done so in this 682 page book.
Conclusion: Lowry was the first to publish it but did not write the lyrics.
Source of the quote above: https://mudcat.org/thread.cfm?threadid=32196
I don't have access to a copy of the book cited above, so I can't verify it myself.