ive only ever heard of transactions not going through when the sender doesnt provide a sufficient fee. couple months ago i sent a tx with 0.000001 as fee and it was still confirmed in like 2 days, so i think its possible for money to revert back but highely unlikely
Why mine i have low fee in electrum then its not confirming and still my transaction running. after 2 days still the tx transaction not confirm. So i dont expect it to get back my send btc to recieve in other wallet but in 5 days my bitcoin tx transaction got back to my wallet...