AbstractBaseOrderableValve line 501
else if (!resolvedSitemapItem.getHstComponentConfiguration().isCompositeCacheable())
and the second .getHstComponentConfiguration evaluates to null because we dont specify anything
The customer if upgrading from a 11.1.0 project to 11.2.4
the page cache is one of the items which has recently been added as a feature. In their setup they have a sitemap item withouth pageconfiguration id.