Yes its a great variety, we were just picking loads of leaves off Grenoble Red sown seven months ago, and we have picked each plant since November. However that non-germination is disappointing. I have had similar problems and now keep my own seed (works best in a polytunnel from overwintered & early-sown lettuce), also Steph just had the same thing with Franchi’s Grenoble Red seed, bought this year, see image below.
You could send a message to Paolo Arrigo grow@italianingredients.com, he runs Seeds of Italy. Seed companies need this kind of feedback because I find their germination figures sometimes do not match what happens in a garden.
This photo shows Grenoble Red from Franchi on left, sown at same time as lettuce from Organic Gardening Catalogue in the other two strips.