The Ombudsman has jurisdiction as it is the Financial Services Ombudsman (not just Banking, but all forms of financial services). The service is free, so opening a case is likely to be way more cost effective, and might prompt a quicker response.
This is without doubt the most effective way forward - the age thing will cause issues I'm sure.....but?????
That's where is gets murky - Palpal will say that the account was opened fraudulently (false age declaration), and I don't know how the Ombudsman will progress things from there. I can't see Paypal having any right, despite the age "inconsistency", to retaining the funds, but I can see they have a fair argument to suspend the funds for a period.