Electronically issued documents legalisation

Does anyone how to legalise the documents which have been issued electronically?

The FCO website states;


PDFs and other electronic documents
You can get a printed copy of a PDF or other electronic document legalised if it either:

has the original ink signature or seal of the person or organisation that issued it
has been certified by a UK notary public or solicitor


https://www.gov.uk/get-document-legalised

I am in a situation where I've to legalise the "Experience Certificates" confirming my employment duration and job title. However lawyers are not willing to do it as they say they need to see the originals.

Unfortunately my document does not have a stamp but just a signature of the HR, all electronically done.

Anyone has been in the similar situation?
Thanks