A Close Shave Issue/Question

[guyinatux]

So I have a main save on PS4 which I got up to 100% however it glitched out and I only got 49/50 bridges. I ran through video guides and tried ever bridge and could not get the last one.

 

I decided to start a new game and do all 50 bridges in one go with a video guide then move onto the knife flights. I get all 50 bridges done but it turns out it is very difficult to get a hold of a Mallard so early in the game. So I decided to play through the story and buy one when I had 250k BUT now the main story missions have glitched out and I can no longer start the Minisub or Cargobob missions for the Merryweather heist.

 

My situation is this: On one save I have 15 knife flights complate and 49/50 Bridges and one another save I have 50/50 bridges and 0/15 knife flights but no Mallard and no means of buying one quickly.

The trophy has not popped and I wonder if it is because both the bridges and knife flights have to be completed on the same save.

 

Any ideas?