I was even thinking if OTHER party members could cast spells on the druid perhaps? I see Telepathy, but that's an 8th level spell!! Could be worth the casting...but very situational.
Helm of telepathy would work I guess...but limited range. I was thinking of scouting out something (as a bat perhaps) and be able to provide information to a party member for example (guide them to a hiding creature etc).
WotC seems to have shut down the thought-stream pretty tightly.