Dropper post with fake top tube bar

hainman

so i bought a Saris bone3 bike rack a while ago,have used it to transport mates HT's but not managed to fit my Giant Reign FS on it,the support arms come in way to close to connect with my frame i dont feel its same to carry it,I looked into the fake top tube bars you can buy but are they safe on dropper posts??I dont want to have to fork out for old seatpost and saddle to transport my bike,as the faffing about to put the post in and try to secure my dropper so i dont need to strip down the cable and switch would be a PITA....any insight would be greatly appreciated