A few thoughts...
1, Each coin/medal has a unique number (unless a mistake is made), but...
2. The certificate number isn't always linked to the minting order (or sales order) - the numbered certificates can be randomly inserted into packages/coin boxes and/or packaged coins can be randomly pulled from inventory.
This means that your coin/medal can include a certificate stating "10/100" but might have been the 5th struck and 50th sold.
IMO, the potential randomness of the process makes it best to not place too much importance on the certificate number unless there is verifiable proof as to exactly what it means.
Collecting history one coin or medal at a time! (c) commems. All rights reserved.