it was never really designed with Quest in mind, but its good to know it mostly works without much changed.
the animation you refer to is set to be played by vrcfury prior to upload. however, that function is part of the SPS component that would have been removed, causing the issue.
fixing it in the way you describe will mostly work, but if someone does not have your avatar 'fully shown' and safety settings have animations disabled, it will still appear fully aroused to that user.
an alternative i suggest, which is easier to perform, is after removing the SPS component, add an "apply during upload" component, and set it to play the "Taperinsideslit" animation prior to upload. this will ensure both that it's the default state, and that safety settings won't interfere with it.
i will take this into consideration for an update i am working on, and may move the pre-upload animation into this separate component, to simplify it for users adapting it to quest.