Gender: boy
School:
School #14B
After an exact search for Heniek Lenga proved unsuccessful, I shortened the search to H* Lenga, and Henoch Lenga was the only match that came up. In addition to sounding similar, Henoch was also born in the right time range to have been the appropriate age to sign the album.
Based on matching addresses, I have determined that Henoch had a father (Pajsech, b. 1898), a mother, (Tauba, b. 1903), and a brother (Schmil, b. 1935). They were all deported on the same date, February 23, 1942, on which date there was a deportation to Chelmno.