A slightly fuller version of events, perhaps?
Prior to the band getting a recording contract (a LOT prior), the band felt they needed to make a series of demo recordings that they could send to record labels with the view of getting signed. Rumour got back to Brian though a friend that a "new" studio was just in the process of setting up, called DeLane Lea, based in the same complex as Wembley Stadium, and Wembley Arena. They needed a loud rock band to test the acoustics, and equipment at the facilities, and in return for this, they would let the band record a number of songs, namely Keep Yourself Alive, Liar, Great King Rat, The Night Comes Down and this very different version of Jesus.
Eventually, the band signed to Trident Audio Productions, based at St Anne's Court, just off Soho Square in London, but only after they'd been turned down by just about every major record label.
The tracks they recorded at DeLane Lea were cut to an acetate (well, several of them, to be exact), and come the release of the 2011 remasters with bonus EPs, the only copies of these recordings the band could find in any decent quality, existed on one of these acetate records that was sat in Brian's personal collection. Hence, what is considered now, the very trendy tracking noise on the beginning of these tracks.
So, as was previously mentioned, they weren't recorded at Trident.
The tracks that came out on the first album WERE recorded at Trident, with the exception of The Night Comes Down, where the version from the DeLane Lea demos was used. So with the version on the bonus EP, they decided to "process" the sound a bit, to give a slightly different version.
Mad The Swine, I think, was scheduled to fit on the first side, between Great King Rat and My Fairy King, however, the story goes that this was an instance where Roy Thomas Baker (noteworthy because John Antony was the album's main producer) apparently did something with the mix that Freddie really didn't like, and because they couldn't reach a compromise, Freddie decided that it wasn't coming out at all then. Time warp to 1991, and the multitrack reel for the song was apparently discovered in the basement of the Queen offices in Pembridge Road by Jacky (yep, fan club Jacky), when her and one of the band's secretaries were doing a sort out of all the stuff down there. The fan club shared the basement with another room that had a lot of the tape cans. Anyway, they got David Richards out in the band's studio in Montreux to sort out the issues Freddie originally had with the track, and it was released as a bonus track on the 1991 Hollywood remaster of the first album. It also came to light as a third track on the extended format releases of the Headlong single (CD single and 12"). AFAIK, the RTB mix remains buried in the archive, and will probably stay there for eternity.
Technically accurate, as far as "I" know. Maybe Sebastian could shed some more light, if I've missed anything, or it's not 100%.
What is left of your dream?
Just the words on your stone.
A man who learnt how to teach,
But forgot how to learn.