The standard past-participial form for the verb shake is shaken. Normally the original Book of Mormon text has shaken (five times), but there are two instances of shook (where the past-participial form is the same as the simple past-tense form). The first instance is here in Helaman 5:42, where the standard shaken was introduced into the LDS text in the 1906 LDS large-print edition. The other instance of past-participial shook was changed to shaken in the 1920 LDS edition:
For both these cases of original shook, the RLDS text has retained the nonstandard shook. As explained under 1 Nephi 5:1, 4 for the past-participial came, the critical text will restore instances where the simple past-tense form is used as the past participle. For a general discussion, see under past participle in volume 3.
Summary: Restore the two instances of past-participial shook, in Helaman 5:42 and in 3 Nephi 8:14.