No.
The context of the quote makes your theory make no sense.
Would he take breaks to work on the U2 record? Was he thinking of that at the same time as working on that record?
Yeah, he definitely was going back and forth. It was kind of fun to be able to hear the works in progress of U2 because I was such a huge fan of theirs in high school.
How's it sounding?
It sounds awesome. It sounds really cool. It was kind of cool to hear that they record in a very similar way to the way that I work, where you improvise and try your best to come up with melodies and stuff but you don't have any lyrics.
I can't wait to hear what he does with them.
Me too. I'm so hoping it's going to do well for both parties. I think it would be great to be a hit.
Is he going to do the whole record with them?
Apparently they've done just tons of material. Apparently that whole first record is just Brian's work.
The entire discussion refers to work on an album. The direct question in which the quote is an answer to refers to "record" in a way that ONLY makes sense if they're talking about an album. Nobody would ask if he was doing "the whole song" with them, as if it were something newsworthy. Directly before Mercer's quote in question he discusses the huge amounts of material they've done. Again, something that makes the "record means song" theory make zero sense.
So yes, when one says "record" it is possible that they're referring to just one song... but in the context of this interview it makes ZERO sense, and is clearly referring to multiple albums.
Whether or not Mercer has any particular insight and accidentally let something slip, or he is just aware that they've worked with multiple producers and assumes there are multiple albums? Yea, those things can be debated.
But in no way is he referring to a "record" as Ordinary Love and only Ordinary Love. The context of the discussion makes that incredibly crystal clear.