Do you still want to have the single four switches as objects separately from the all-in-one switch?
If so, that's definitely possible (I'm thinking make it flag based i.e. any switch object becomes a all-in-one switch if it's in a specific translevel) but it's the harder thing to do so I'll ask before doing it.
If you're fine with only having the all-in-one switch, here's a quick patch that makes any of the switches activate every one of them:
Code!addr = $0000
if read1($00FFD5) == $23
sa1rom
!addr = $6000
org $00EEAA
LDX #$03
- LDA #$01
STA $1F27|!addr,x
DEX
BPL -
LDX #$00 ;color of the pressed switch sprite (0 = g, 1 = y, 2 = b, 3 = r)
NOP

DIDN'T TEST

BACK UP YOUR ROM FIRST

e: added SA-1 blabber