In the documentary, it shows clips of footage that has never been seen before. Bob Weir (Guitarist) confirmed this in episode 2 of the 6-Part documentary.
The ice-cream flavor mentioned as being named after Jerry Garcia is "Cherry Garcia" from Ben & Jerry's. It was introduced in 1987 and remains one of their all-time best-selling fan-favorites to this day. It's cherry ice-cream with fudge flakes and pieces of cherries. Variations on the flavor have since been made available, such as non-dairy and frozen yogurt, and some for a limited time as a "limited batch", such as "Chocolate Cherry Garcia", made with chocolate ice-cream.