It does not mention interior/cave. In fact, the secret money was only given once when I placed it on an interior DMap (at least in 2.5). But when I tried it on a dungeon DMap in 2.5, it was only given once, meaning that the secret money behavior in 2.10 has since been fixed. Another room type that never seemed to disappear on the Dungeon DMap in 2.10 is the Red potion or Heart Container Room Type.Secret Money
When the player steps on the Rupee in the center of the room, they are given a number of rupees equal to the screen's Catch All value. Secret Money screens should only give rupees to the player only once - however, in version 2.10, if the current dmap that the player is on is a dungeon, this is not the case.
By the way, the door repair room you see here is on an interior DMap.
Perhaps there should be a Door Repair [many] room type and a Secret Money [many] room type, to replicate the 2.10 behavior. However, the Door Repair room type we have now would then be Door Repair [once], and the Secret Money room type we have now would then be Secret Money [once]. Basically, Door Repair (once) would only charge the fee only once, while Door Repair (many) would charge the fee every time Link enters the room, and Secret Money (once) would only give rupees to Link only once, while Secret Money (many) would give rupees to Link every time he enters the room, as the rupee would reappear every time he enters the room.
PS: After 2.5, maybe there should be a room type editor along with the combo type and combo flag editors.