We're continuing to work on this, but in the meantime we know this stall is really frustrating for those of you experiencing it. Our current plan is to get a fix completed and live in a hotfix tomorrow (May 22). For now, we have temporarily set the affected event to instantly succeed rather than stalling out. This will allow you to progress to the next steps rather than trying to find a map that is not stalled. Once the fix is live tomorrow, we'll revert the event progression back to normal.
Thank you for being patient as we work on this!