Complex sentence: This rumor was established due in part to the fact that Scarlet's vocals sound reminiscent of Criss' early vocal contributions to Kiss, along with the fact that Criss was thanked for his contribution to Trouble Walkin.
Split into simpler sentences: This rumor was established due-in-part to the fact that Scarlet's vocals sound reminiscent of Criss' early vocal contributions to Kiss. This along with the fact that Criss was thanked for his contribution to Trouble Walkin.