How to post pictures via API?

So I thought I’d try a different approach by using the S3 storage. I followed the instructions here to setup an AWS S3 bucket. Here are my settings:

And here is my code:

	async uploadExternalImage(imageReferences: string[]): Promise<string[]> {
		const imageUrls: string[] = [];
		for (const ref of imageReferences) {
			const filePath = this.app.metadataCache.getFirstLinkpathDest(ref, this.activeFile.name)?.path;
			if (filePath) {
				const file = this.app.vault.getAbstractFileByPath(filePath) as TFile;
				if (file) {
					try {
						const url = `${this.settings.baseUrl}/uploads/generate-presigned-put.json`;
						//const imgfile = await this.app.vault.readBinary(file);
						const img = {
							type: "composer",
							file_name: file.name,
							file_size: file.stat.size,
						}
						console.log(JSON.stringify(img));
						const headers = {
							"Content-Type": "application/json",
							"Api-Key": this.settings.apiKey,
							"Api-Username": this.settings.disUser,
						};
						const response = await requestUrl({
							url: url,
							method: "POST",
							body: JSON.stringify(img),
							throw: false,
							headers: headers
						})
						console.log(response.json)
					} catch (error) {
						console.error(`Error uploading: ${error}`);
						//console.log(response.json)
					}
				} else {
					console.error('error')
				}
			} else {
				console.error('error')
			}
		}
		return imageUrls;
	}

Now, I realize this currently won’t work because I’m not actually uploading the file yet. From what I read in the docs, I would send a json object containing the type, file_name, and file_size. The api should reply with a key and a url for me to use for the actual file transfer. But at this point, I’m getting the following error:

{
    "errors": [
        "The requested URL or resource could not be found."
    ],
    "error_type": "not_found"
}
[
    "The requested URL or resource could not be found."
]

I looked into my API key to make sure it had permissions, it does. But I created a new one anyways. And a global one. None are working. Same error code. What am I doing wrong?

Edit, here’s the img object:

{"type":"composer","file_name":"face2.jpg","file_size":17342}