Contact Cleaner while flammable, friction I have yet to see ignite it. We use lots of it at work because we have some electronics from 1987 still running and critical to the business, and the contacts are no longer shiny gold but a dull color. We have only had 1 fire with contact cleaner to which a employee was spraying contact cleaner into an E-Stop to try to clean the contacts inside and exercise the switch, and in the process there was a spark in the contact from the 24 VDC and it almost took the technicians eyebrows off because he soaked the contact blocks in about 10 seconds of spray volume to which upon a spark there was a quick fireball that came and went because contact cleaner has a rapid evaporation rate. When I use contact cleaner I plug stuff in at full arms length away because even unenergized equipment could have a static spark and I care about retaining my facial hair.
If its the gold pads that are dull in color we use a pencil eraser on them to shine them up and make sure that all rubber fragments are off the board before inserting into assembly.
For your situation DO NOT USE AN ERASER because you have fragile gold pins that can be easily damaged in the RAM slot that you are worried may have a contact issue with new clean contact pad RAM. Usually blowing canned air in a memory slot will blow out any contact problems and the new clean gold pad of the RAM stick makes a good contact due to jaw pressure of the RAM in the slot on desktop boards and inserted and leaned to the locking wings on a laptop.
Only concerns with using contact cleaner is that we have noticed that some plastics are not compatible with it and so for example a light barrier in a machine with a clear plastic lens that a photocell beam shines from emitter to detector, if contact cleaner gets on the clear lens it will react with the plastic and make it permanently cloudy as the surface is chemically melted through an interaction. In a memory slot though if the plastic was not completely compatible with the contact cleaner spray it might just discolor the memory module socket and evaporate.
