failing to convert from webp to jpg

[aner87]

Hello everybody,
I'm having hard time understanding how I can convert a WEBP to JPG format with this library.
Here's the code that I am trying out, attempting to get a chart I created with image-charts, saving it to WEBP (which it seems like working) and then converting it to JPG (which doesn't work...):

const fetch = require("node-fetch");
var webp = require('webp-converter');

fetch('https://image-charts.com/chart?chs=800x500&chd=a%3A9013.2091736%2C9163.2091736%2C9165.06157621%2C9161.66901514%2C9170.42788996%2C9169.43452831%2C9182.01273139%2C9194.16973332%2C9168.5367712%2C9186.19727611%2C9176.0191636%2C9179.57585269%2C9161.28960878%2C9239.28629898%2C9236.19102544%2C9268.5816066%2C9287.45653125%2C9285.54630386%2C9285.66476772%2C9350.08109775%2C9378.11735531%2C9335.07726903%2C9323.07942068%2C9311.25715813%7C1%2C2%2C3%2C4%2C5%2C6%2C7%2C8%2C9%2C10%2C11%2C12%2C13%2C14%2C15%2C16%2C17%2C18%2C19%2C20%2C21%2C22%2C23%2C24&chxt=x%2Cy&chxr=1%2C8513%2C9878&chxl=0%3A%7C23%7C22%7C21%7C20%7C19%7C18%7C17%7C16%7C15%7C14%7C13%7C12%7C11%7C10%7C9%7C8%7C7%7C6%7C5%7C4%7C3%7C2%7C1%7C0&chls=5%2C0%2C0&chtt=BTC%2FUSD+Powered+by+%40crypto.rates&chts=C04F1D%2C20%2Cr&chco=C04F1D&chma=20%2C20%2C20%2C20&chg=0%2C50%2C3%2C5&chm=s%2CC04F1D%2C0%2C-1%2C15%7CB%2CFCECF4%2C0%2C0%2C0&cht=lc')
    .then(async res => {
        const dest = fs.createWriteStream('./lastPicW.webp');
        await res.body.pipe(dest);
        console.log("image saved as WEBP...")

        webp.dwebp('./lastPicW.webp', "./lastPic.jpg", "-o", function (status, error) {
            if (status == 100) {
                console.log("Image saved as JPG!")
            } else if (status == 101) {
                console.log("Saving as JPG...failed!")
            } else {
                //if conversion successful status will be '100'
                //if conversion fails status will be '101'
                console.log(status, error);
            }

        });
    }).catch(err => console.log("fetch err: " + err))

Any idea on what I'm doing wrong? Thanks =)