This will depend on the nature of your relationship with the landlord and the type of deal you wish to do.
Can you provide me with additional details please.
Are you a tenant or licensee? Is there a lease?
What deal ate you proposing to enter into with the 3rd party?
I look forward to hearing from you.
Thanks for providing further details.
Sadly, I think that you are not in a strong position here as you have given notice to terminate your lease (without sight of the lease and notice no comment is made as to your lease or the notice served to terminate it) which your landlord has accepted as valid.
Legally you cannot force the new tenant to do a deal with you on the goodwill/fixtures and fittings. Al you can do is to try to contact the prospective new tenant to see if they will buy the goodwill and assess. If they are to operate as a cafe the new tenant may want the assets. But like I said there is nothing you can do to prevent to new tenant dealing with the landlord direct.
Whilst not the news you were hoping for I do hope that this helps.
Please can you accept/rate my response so that I receive credit for the time I have spent assisting you.