Command to reproduce in a command block with light:
/setblock ~ ~1 ~ spawner{SpawnData:{entity:{id:"minecraft:creeper"},custom_spawn_rules:{sky_light_limit:{min_inclusive:0,max_inclusive:15},block_light_limit:{min_inclusive:0,max_inclusive:15}}},SpawnPotentials:[{weight:1,custom_spawn_rules:{sky_light_limit:{min_inclusive:0,max_inclusive:15},block_light_limit:{min_inclusive:0,max_inclusive:15}},data:{entity:{id:"minecraft:creeper"}}},{weight:1,custom_spawn_rules:{sky_light_limit:{min_inclusive:0,max_inclusive:15},block_light_limit:{min_inclusive:0,max_inclusive:15}},data:{entity:{id:"minecraft:husk"}}}]} replace
Expected outcome: spawn both of those mobs with light rules