Puppy might be chewing pee pads

So my 4 month old puppy has been doing well with potty training and pen training until recently. I work 12 hour shifts 4 days a week and am paying my best friend to come take him out to go outside at minimum 2 times a day. So he goes out at 5am(quick pee) 6:40-7:10am (long walk/ sniff time), around noon (walk/play), between 4-5pm (walk and play), 8:30pm(quick pee before dinner), around 9pm (semi long walk/sniff time). He normally only pees on the pee pads in his pen once throughout the day and normally leaves them alone. Today when I was looking at the camera to check on him I saw him dragging the pads around his pen area and it looked like from my angle that he was chewing on the corners. My friend will be there in a few minutes and has been instructed to just remove them and not put new ones down for now. I guess my questions after this long winded explanation is: Can I spray bitter spray on the puppy pads or would that deter him from using it if he needs to? His pen is on vinyl flooring so its not that big of a deal if I need to just stop using them because I mop his pen area every night with enzyme stuff anyways. Also I would like to add that he does have a plethera of toys available to him in his pen (I did take out the teething keys he had because he chewed off a piece and choked when I was home but he does have kongs that get filled and freezed so he has one everyday)