Set ForumThread LastUpdatedDate via Automation Studio (core_v2_forumThread API)?

Apologies if this question is duplicative but my search-foo has failed me. Is there a way to either explicitly set the Last Updated Date (so as to not trigger Activity Story or user Unread status) of a forum thread when updating the thread type via API or suppress the Activity Story and Unread Status change from an automation event?

Situation: Trying to do essentially the opposite of this:  Option to Convert Questions into Discussions where we have forums that have predated the existence of Question/Answer format and we'd like to convert them to using the Q&A format so we can better keep track of threads that need attention or a definitive answer. (Scale is hundreds to thousands so individually opening each one and clicking is a rather unattractive workaround)

Using the API in Automation studio, I can successfully get the list of the threads, use the forumThread.Update method to change the type (and even ensure the post date stays the same) but in testing it is flagging everything as unread for users and is surfacing activity stories based on the update date (time I trigger the Automation).

It feels similar to TE-17806 mentioned here in REST context:  Is it Possible to Programmatically Override Activity Story LastUpdate Date on Creation? but I don't see a documented method for setting the LastUpdatedDate within the core_v2_forumThread.Update API

If this is something best done at the database level, that's an option, but one that I was hoping to avoid if possible.