No. If a monkey inherently NEVER, EVER hits one key at a time, then I gu3ss that scenario would make it impossible but that's just stating that something is impossible in the first place and doesn't affect the actual thought experiment in any way. Assuming that the typing monkeys literally ever have the possibility of only hitting one key at a time, no matter how many times they press two keys at a time and type nonsense, they will eventually and necessarily, bc of the definition of infinity, type Shakespeare. I don't know how I can explain this better but I'll try later when I have some time.