Ok, so the “Have you read this similarly titled post” was actually helpful. I inferred from this post (LZW30-SN - Multi-tap improvement) that if you disable the delay on the switch, you lose multi-tap (presumably transformed into a favorite button followed by the regular to trigger the multi-tap). I re-enabled the delay and now multi tap is working. Posting for anyone else who comes after.
A notice of loss of feature or changes would be much appreciated when changing this setting.