Nope. Can't see the images of the PCN. However, FYI, it matters not when you actually received the Notice to Keeper (NtK). What matters id the date it is deemed to have been "given", which is two working days after the date it is issued.
So, for the purposes of trying to figure out whether the NtK was given within the relevant period as defined by PoFA, if, as you say, the alleged contravention occurred on Wednesday 18th June and the NtK was issued on Monday 30th June, then it was deemed given on Wednesday 2nd July. By my calculation, that is exactly 14 days and within the relevant period.
However, you can put them to strict proof of the actual date the NtK entered the postal system as they are required to be able to show this, according to the PPSCoP section 8.1.2(e) Note 2 which states:
A notice sent by post is to be presumed, unless the contrary is proved, to have been delivered on the second working day after the day on which it is posted; and for this purpose, “working day” means any day other than a Saturday, Sunday or a public holiday in England and Wales. Therefore, parking operators must retain a record of the date of posting of a notice, not simply of that notice having been generated (e.g. the date that any third-party Mail Consolidator actually put it in the postal system.)
Considering that all these firms use mail consolidators and do not use 'first class' service which is guaranteed a 1-2 day service (2 day service) but rather a second class service which only guarantees a 2-3 day service (3 day service), then they would struggle to show that the NtK was given within the relevant period.
Then again, we have not seen the NtK so this is all hypothetical for now.