The only frame on the nacelle is at the inlet side, forward of the fan housing (and attached to it by multiple bolts, which I can not see in the picture). The thrust reverser has two half-circular frames, but I would expect more systems parts installed to it, which are not present. Looking at the RR logo, I would assume this is a piece of the forward inlet frame. It is highly unlikely that engine debris would hit it, so I would assume shrapnel damage from the front side as most probable. On page 6 of this
brochure you can see the according frame in the lower left picture.
Fits the other damage, if this is the port side engine nacelle frame.