Jovial, ESPOL/NEWP, PL/I, PL/S, BLISS and a couple of others did exist and were in active use outside Bell Labs.
Even Multics actual history was only a failure from Bell Labs perspective, as they went on and were even considered more secure in a DoD security assessment.
Even IBM did all their RISC research in PL.8, before deciding to create what would be AIX, as by then it was all about UNIX workstation market.
Had AT&T been allowed to sell UNIX from day one at the same price as competing OSes, I bet C wouldn't be around.