HELP* APPLICATION* Sending in GCSE Certs for foundation year

Hey guys, long time lurker and in need of some advice.

So I have applied for English with foundation yr at Durham university. They were happy with my cv which explains my poor gcse grades and vocational experience and obvious interest in reading and English. Shortly after, I had to do an interview and then complete some questions and a small essay on a source emailed over to me.

Fortunately I have passed that as well and have received an unconditional offer via track ucas.

When applying I only listed certain grades such as English lang, media and not many others pertaining c's. I got a D in English lot and terrible grades overall.

I'm 21 and will need to spend £301 to replace all certs I think. But will my other bad grades derail my possibility of studying at Durham?

According to their foundation entry requirements:

"""""We welcome applications from:
UK and EU students
Mature learners (over 21) with no formal qualifications*

*Some programmes require GCSE Maths at grade C.
Formal qualifications are not normally required for UK students. Evidence of academic qualifications is required
for EU students. It is desirable for candidates to have achieved a C or greater in GCSE Maths (or equivalent).""""

If I send them will they be okay with them being bad?

Sorry if I'm coming across frantic, I feel some anxiety and skepticism for my dream coming true to study there

So you didn't declare all your GCSEs?

Not all, only ones with c's. Thought it would be pointless to pout d's. Their site does say "Formal qualifications are not normally required for UK students."