Cool, there are a few ways you can achieve this.
Quick question, are there more than 1 admin account?
If there is 1 admin account, then you can use rules on the fields/sections that you don't want to be seen/edited after the form is submitted, and more rules on the fields that only can only be edited prior to the form being submitted!
I've attached a quick form that demonstrates some of the concepts.
Firstly the Problem section has a ProblemUser field that gets the current users user ID using the user() function, this only updates when the form is created. This field is read only.
Secondly, the Solution section has a SolutionUser field that updates every time the form is opened. This field is read only.
Thirdly, the Solution section is set to hidden if the SolutionUser is not RaYvA.
What this does is allows anyone to open the form and fill in the Problem section, but only RaYvA can see the Solution section.
There is an additional rule on the ProblemInfo fields that disable them if the FormName field is populated (which should be populated when the form is submitted).
As I said there are a number ow ways to achieve this, this is one quick and dirty example :)
Hope this helps?
Cheers