Connecting to P1 from random WiFi

I am not familiar with Particle P1 and it's cloud solution, I hope someone here can help me with a question.

A particular equipment is equipped with Particle P1 and can be operated with the manufacturers proprietary app, I assume using the cloud solution from Particle.

I would like to operate the equipment using a more open cloud software, but I have no idea if this is really possible (the maker of the "open" software cooperates, and has already integrated similar equipment from other manufacturers).

The USB port on this P1 board is left intact so I have been able to decode the commands from the app using the Particle CLI software (Windows).

The missing part is to be able to control the P1 over WiFi. The manufacturer of the equipment is not willing to help, so I assume it will be difficult to get any further.

Is there any way to connect to the P1 using WiFi in a case like this?

Regards,
Jan

It is not possible without the manufacturer's cooperation. Presumably the device is connected to the manufacturer's product, and only that account can control it over the Internet, or remove it from the product so it could be attached to a developer account.

Thank you for the clarification, unfortunately as I expected.