134 in a 1234 system?

My “knowledgeable” friends at a Nationally Known Auto Parts Store told me that 134 refrigerant was needed for my Ram 1500. I hooked up the can and gauge but couldn’t get a good connection or a pressure reading. I did set off the refrigerant can because it got quite cold in my hand. After realizing this was the wrong coolant, I called my local dealer and he said that I likely contaminated my whole system and may need to replace everything. A mechanic friend of mine doubts this and believes that I just blew the coolant into the air because the hookups aren’t the same. So, I know I screwed up, but how much did I screw up. Do you think I actually got 134 coolant into my 1234 system and contaminated it with just an over the counter can of 134 refrigerant? Thanks!