The Guardian quotes the Belgian Prime Minister as saying (complaining) that the Walloons "radicalized" their position during the course of the discussions. ( https://www.theguardian.com/world/2016/oct/21/eu-canada-ceta-trade-deal-meltdown-canadian-minister-walks-out) In other words, it doesn't seem they were negotiating in good faith and protestations that more time was needed seem disingenuous.