No good explanation for this? The committee was taking procedural votes on Cline's amendment and Steube's amendment to HR 8 in 2019. Cline's was ruled non-germane and he refused to take it off until they could do the next committee hearing. Steube kind of parlayed that into "how much of a social media push can I get with mine?" and didn't want to take his off. Matt Gaetz was actually the first congressperson to "meme" it out to everyone.
Two weeks later, Collins inserted it as a rewrite and it passed with Democrat support.
H.R.8 - 116th Congress (2019-2020): Bipartisan Background Checks Act of 2019
The better story is that once the bill was finalized, WITH THE ICE NOTIFICATION AMENDMENT IN THERE, all House Democrats except 2 voted for it, while all House Republicans except 8 (Will Hurd being one) voted against it.
Oh, and of course, Mitch wouldn't even put it on the business of the Senate.
This partisan back-and-forth and the sadness of the two who tagged it "Winner" shows a lack of understanding on several fronts.