The claim of a forming planet is nothing more than the hypothesis that the emission is a result of a circumplanetary disk of gas orbiting a gas giant about three time the size of Jupiter. A similar claim had been made before form around this star in the form of a faint blob of gas at about the distance of Pluto from the sun. Even with this large star are according to planet formation theory, a planet should not be forming that far out however this could simply be a Jupiter size planet with some gas and dust around it.
The star have a disk of dust and gas orbiting it, but the logic behind the claim of forming planets is the assumption that planets and stat actually form from dust and gas in space. The theory generally referred to as the Nebula Hypothesis is a purely atheistic theory of the origin of stars and planets, that was specifically designed to explain the existence of stars and planets apart from God. The theory that has problems requiring repeated patching to protect it from reality. The reasoning behind this claim is that planets form discs of dust and gas around star, so finding evidence for planets inside a disc of dust and gas around a star gets interpreted as forming planets.