Collection 192 is difficult, you only get the collection items when you defeat the pyramid as one of the top 3. To enter the pyramid you need 40 keys which only drop now and again when defeating very coin expensive skeleton sacrificers and conquistadors. Even high level friends will want to keep these collection items rather than gift them plus charging this collection doesn't drop keys for the pyramid.
With that said collection 192 is only really required for keys to the ice castle as no other collection drops those. It is also the only collection that drops keys to the bunker but as you only need 5 to enter its easier to keep banishing snatchin knights or guardsmen, the drop rate for keys is decent and chocolate medals drop in 2s when searching rooms.
You can get 100 keys to necromancer and vampire rooms with collection 212 but you need to be patient as you will need to search the mystical living room a few hundred times just to get enough chargers, however this is more realistic than collection 192 being charged once let alone 4 times.
Keys for reanimator should be easy enough to come by with collection 206 giving 50, again just keep searching enough rooms to get the drops to banish the snatchin resistance fighter and partisan who drop the collection items. Collection 192 does not give these keys either. The minions and lady eustece which roam yards also have a decent non-expensive drop rate for the keys.
Finally the hyperion room needs keys which no collection drops, like the pyramid keys, for these the snatchins that drop reanimator keys are a good bet as are the troopers who only require two rifles to banish.
I would focus on bunker, necromancer, reanimator and possibly vampire rooms to begin with, don't bother aiming for the others unless a quest requires it and then just spend the diamonds needed.
All this of course is pointless to attempt without running a golden turtle of luck.