I'd go one step further and say yes, we lost because of that sub.
We may have been pulled back to 2-2 without it, but I honestly don't think we'd have conceded three if Deulofeu had been brought on, or even if Lennon had stayed on, knackered or not.
I've had time to reflect on it and I actually think that that sub is hands down the worst sub I've ever seen an Everton manager make. It made no sense and never had a prayer of succeeding, and the fact he's paid to make that call when quite literally anyone else would have made a better one is mind boggling to me.