I'm going to Penang next week to renew my non imm B. Unfortunately, my employer forgot about the WP3 in Penang and there is a delay that will overrun my visa, but only a little bit.

My question is: Can I overstay less than a week and take care of it in Penang or is that just a bad idea? Thanks!

It's unlikely but if you get caught, fined and deported you'll probably think so. It's a 'at your own risk' situation.