Workflow automation isn't triggering emails

I am having a crazy hard time getting this workflow automation to trigger emails! I've tried it as an alert and an update, I've tried deleting and re-entering it, I've tried changing the field that triggers emails showing up in Smartsheet itself, or in users' email inboxes.

Here's the workflow:

The "Hand Off to PADL" column is column type "Checkbox", and is set to "Restrict to checkbox use only."

The "PADL Contact" column is column type "Contact List".

I've tried adding new rows directly into the sheet, then checking the checkbox, and also submitting new rows via the associated webform, then checking the checkbox. I've also tried changing the Condition to "Where Service Type is one of", and then selecting "1. Product Training" rather than entering it.

I am so stuck! Any ideas or advice?