You don't mention whether you've simply 'wet-played' - or combined
that with a detergent clean.
The fact you reduced the 'battleground effects' indicates that your
Iso-Alcohol method was leaving behind residues.
The 'crackle' may well be 'permanent' as Alcohol will damage the vinyl
- even with just one 'clean'...this is my experience (shudder)

The method following is 'mine' - & on an initially 'totally noise-free
disc' will create no deterioration whatsoever.
It relies on through-cleaning - and no 'cross-contamination' (as on
commercial RCM's) from disc-to-disc using shared 'brushes' for
solution application - or 'pads' leaving residue/contamination behind
in the non-vacuum types.

1x Plush Velvet cleaning pad (ie type seen in those feeble Carbon-
Fibre cleaners with the centre pad) - I once used the old 'Emitex'
cloth...the Milty DuoPad will also do the job - although the material
eventually comes adrift from the foam base.
Detergent - as above.
1: Damp pad and clean-off both LP sides. Rinsing pad.
2: Apply detergent to pad - small amount.
3: Holding LP with one hand against body (it's not really a good idea
to use the TT..) clean in 4-5 'sectors' half-dozen times - then, when
the foam has built up - in just 3 sectors. Rinse off pad - do other
side. You can apply quite a degree of pressure without damage.
4: Prior to detergent removal 'even up' the solution by one 'swish'
round the LP side.
5: You (preferably) need a fine stream of lukewarm water from the tap.
Hold the LP under the stream - which should 'land' on the dead-wax
area - to the RH side and you'll see the detergent being washed away -
with 1970s vinyl it quickly forms an 'edge' and rotating the LP anti-
clockwise (ensuring water/detergent is not passed onto the LP from
your Pinkies - it can be done..) carry that edge all the way back to
your start-point...then lift the LP up - moving the water stream the
LP edge - then remove.
The LP should be bone-dry You can continue the above method to
complete a second revolution - as, depending on water velocity/
detergent/rotation speed you could leave behind a slight detergent
trace - though the LP would appear dry.

Using this method there should be no need to wet-play the LP's - so
the question of 'distilled water' doesn't arise.
What wet-playing does is to put existing contaminants 'into
suspension' - hence reduced background noise.