Can I submit a small industrial PHP project for architecture validation?

Question

PHP

At some industrial enterprise, the only programmer developed software and now the developer himself wants to check its "quality". I would like a look from more experienced colleagues.

There are no complaints about the work of the software, everyone is happy and happy, but it was done in a hurry, and therefore only some parts are beautifully implemented. The entire volume of the written code is about 5 thousand lines, including the html layout of the forms. Of course, a detailed explanation and the opportunity to delve into the project are attached.

Have you ever faced such a question? Is the game worth the candle? Where/to whom would you give such a project for review? Question price? Doesn't it smell like "students"?

The system solves the problem of marking goods and provides workers with a ready-made graphical interface for managing machines and other equipment in the workshops. The system can:
- receive barcodes/products and their details from an existing ERP
- receive tasks for production and labeling
- manage printers/markers/rewinders/scanners/vision cameras and other specific equipment
- store all errors and results of its work in the database
- give back to ERP everything that is required

Answer 1

It all depends on the goals - for yourself (if you are a developer or you are implementing something written by someone) and your peace of mind or for reporting and certification.
If the first is why not, there are companies, google, especially since your project is quite small, there are even freelancers offering such services... the quality of the result will in any case be random and almost independent of the cost (but you can talk to several independent specialists, so to speak, take the quantity and not the quality). You will also need an appropriate level of knowledge to at least understand the answer and, most importantly, draw the appropriate conclusions and choose the next actions, what will you do if you are told - 'the code is shit, full of holes, buggy, this is where the business logic will break, etc. Is it easier to rewrite than fix?
If the latter, then everything will depend on the requirements of this reporting, and there the method of conducting an audit will be determined by the availability and accessibility of companies to meet these requirements.

Answer 2

There are no complaints about his work, everyone is happy and happy, but it was done in a hurry,

...

and now I want to check its "quality".

"You either take off the cross, or put on your underpants ...", this is not for you specifically, but in general for all such customers. Do I understand correctly that the customer was aware that the deadlines did not correspond to the requirements for this task?
You can easily contact the developer and ask what code he has sketched out on his knee and without tests, and what is written according to the mind. Themselves after all, I suppose the rush and agreed? Well, most likely everything is according to the principle - "quickly, efficiently, cheaply - choose any 2 options!". And what is the point of checking a product that is obviously quick-slapped?
If you have doubts about the quality of a hastily scribbled product - just contact the developers, ask them to write what can be improved / rewritten normally and how much it will cost. Most likely it will be faster and cheaper than any examination. Moreover, the main task has been solved, and you can no longer drive on time.