Yes, they could be SPX90's (1985), as the UP+DOWN buttons look right but I'm not sure about the LED positioning - even zooming in it's too hard to see properly:
https://en.audiofanzine.com/multi-effec ... 17730.html
Good call on the Lexicon PCM41 (and good eyes!
Below it is a MXR Digital Delay Model 113, with memory expansion from the original 160ms to 640ms (or maybe even 1280ms), hence the black overlay around the buttons showing the extended delay times. Then a MXR Flanger/Doubler Model 126 = awesome box!
The 2U grey thing is probably some stereo 4-band parametric or compressor. Bel, Symetrix, Rane and Orban did some grey gear with white knobs but nothing I recognise that looks like that with curvy lines.
The 2U below it is perhaps just a blank panel (or see below).
The 3U black rack seems to be some kind of 80's modular FX type rack, like dbx 900 series or Rebis or Scamp rack (but that is 5U), although it looks like none of them; sure, 905 parametric has six knobs but they're
central, whereas these look too far to the right and have an extra white dot/knob/screw at the top. And the left pair with three knobs don't match any dbx 900 series. Possibly Tanrack? But the six knobs don't match that.
[I think the grey BO0 is some kind of watermark/writing on the photo as it doesn't line up with the slight angle of the rack unit.]
The bottom 2U is too vague to see; he needs a Dimension D in there but its distinctive buttons are not visible. Lexicon 224 is all black but 4U, so not right; you'd see the blue stripe of a 300L, so not that either. I doubt a Roland R-880 reverb (1989) existed yet.
Ask yourself what else he'd need, back then - what is missing? Delays, flanger, comp/EQ are covered, maybe multi-FX. I can't make out the things atop the rack, but I guess some kind of small mixer and maybe PSU/preamp.
I'd bet the two black 2U are power amps, as mostly blank front and a hint of handles either side, with the mostly empty 3U modular in between giving some cooling space, but not a Roland SPA-240 as you'd see the white writing.
JBL monitors, possibly Beyer DT-100s on the old joanna?
And I think that's the drummer from Genesis, no?