Does anybody know, whether the scores in an English test (IELTS / TOEFL) that are required for an entry at cambridge or oxford are definite?
If you received a conditional offer that is subject to a special result and failed to get that result closely, will they insist on that condition or will they let you take the place?

If you have had any info, I'd be pleased wether you could share it...

If you didn't get the result they asked for, I don't know why they would take you. A conditional offer is just that: you must meet the condition in order to be accepted.