What we need to do is first see if that purchase order was ever included in any batch. To do that open the purchase order in Connectwise, open the Products tab, and in the list there's a column for the Batch ID for each product (in the case of products the batch id goes in each individual product in the order because purchase orders can be partially exported).

If they Batch IDs have values then that'll tell you they had been exported and when (the batch number is the date and time). If they're empty then they have not  been exported, so it's either sitting ready to export or maybe they products haven't yet been received (which is what makes the purchase order ready to export).