Genitan. Ive killed it....can I save it?

As Im a sucker for blue or purple plants I bought 3 beautiful Genitans @ £5 each (which is a lot for me living on a tight budget) at a local garden centre and asked about care. Was told good drainage and that they'd behave just like Bell/Balloon flowers (cant remember proper name) so I planted them and they really were not happy so lifted and put in terracotta pots with a good handful of perlite added. They slowly declined and are now almost dead so looked online to discover that they need Ericaceous soil!! I was not told this. How can I stand any chance of saving them? Obviously I will change the potting medium but should I dead head, cut right down or have a funeral?

 

Thought I read that wrong but "n" and "l" are close in the alphabet!

 

Some gentians need acid soil some don’t Cindy. What variety do you have?
Repot in acid soil .....I would use John innes ericaceous compost.
Cut off dead bits and give it a liquid ericaceous feed
Balloon flowers/platycodon are really nothing like gentians except maybe for colour.

 

I meant Gentian of course! Ive no idea which one. It just says gentian. its this one, I took the photo when I first got it