Except, they're not-
Manor are entering with at least 1 Ginetta,
Dragonspeed are entering with an unknown chassis,
SMP racing are entering with a BR Engineering Dallara. These are just the confrimed teams. You're right that Toyota are the only
hybrid lmp1 yes, but not the only lmp1 team. And if you missed it, the class is no longer being counted as two separate divisions, as in no distinction between hybrid and non-hybrid as they'll compete for the win with new rules to make the non-hybrids faster than ever.