If you are unable to retrieve your photos from iCloud or iTunes and you are concerned about using third-party software to recover them, the best course of action would be to contact Apple support directly.
You can contact Apple support through their website, by phone, or by visiting an Apple store. Explain your situation to them and they should be able to provide guidance on how to recover your photos, as well as any other data that may have been lost due to the water damage.
In the meantime, make sure to regularly back up your iPhone's data to prevent future data loss. You can use iCloud or iTunes to back up your data, or you can transfer your data to a computer using a Lightning cable and make a backup on your computer.
If none of it works then try any of the third-party iPhone data recovery software on your Windows. Some of these software gives you the option to scan your device for free and can show the preview of the recovered photos and videos. If you find the required media files in the preview then you can purchase the software to save the recovered data in the local storage of your laptop.
There are several data recovery software programs available that can potentially help you recover your lost iPhone data like Stellar Data Recovery for iPhone, Dr. Fone, Phone Rescue, etc. It is important to note that data recovery success depends on various factors, including the severity of the data loss, the condition of the device, and the length of time since the data was lost. Therefore, it is always best to try to recover data as soon as possible and to stop using the device to prevent overwriting the lost data.
Let me know in the comments if any of it worked for you. Wish you the best for media recovery.