PHP Expert with knowledge of Ajax/JS needed

I have a project which is a CRM built in Wordpress customised with custom code utilising PHP, JS (Ajax specifically), and a SQL export query.
We have a few bugs in the system that need working out plus a SOP for how to fix these issues should they arise again in the future.
We have moved the CRM to another URL which may be the cause of the SQL export failing.
The Ajax is causing a database time out.
The project will be awarded to someone confident in Wordpress AND JS/PHP/SQL.
Further specific details will be provided.
Please provide examples of how you would begin troubleshooting this issue. We can jump on a call to talk through the issues if required.
Budget is flexible for the right person.
Please start your proposal with the word CHEESE so I can check you've read the entire brief.