I was going to ask about the clown. I think I would leave well enough alone and just watch for the next couple of weeks. Do try offering food on a stick near the den daily. A short arm is the sign of predation, a curled up arm (third on the right - clockwise as you orient your eyes with the octos) is the implication that the animal is male. Here are a few photographs of the curled up hectocotylus of several species. I can't tell one way or the other from the video as they will curl all their arms at times. The specialized arm usually remains tightly curled even when the other arms are hunting.
Ok ya the shirt arm was on the left side not the right so I think Taco may be a female.
I have a nest cam which records the tank 24/7 and haven't seen any sign of anything for at least three days. No substrate disturbance, no food eaten, nothing. I'm concerned. Any other steps I should take at this point?
Test your water daily and watch for an ammonia or nitrite spike that might suggest she has died. If you can arrange a peaking doorway (removable rock that does not fully disrupt the den), you may want to try setting this up. Some of mine allowed an opening large enough to view within, others have insisted on closing the den up completely. Ensuring a gentle flow of water to Taco and the eggs may help.
Brood times vary highly with species and water temperatures. For the aquarium sized animals, large egg species tend to more eggs and a longer brood time than small egg species but the colder the temperature, the longer the brood cycle. Even though a GPO lays small eggs, they have the longest hatching times for aquarium kept octopuses (roughly half a year -- the longest brood time was recently estimated at 3 years for an arctic species observed with an ROV, egg size not mentioned/known). Start watching for hatchlings after 3 weeks but it may be considerably longer. Guessing from the size of the octopus, there is a fairly good chance the eggs are fertile. Sadly, there is almost no chance any of the hatchlings will survive. The full hatching may take a full week but three days is the most commonly observed with the majority hatching on day 2.
Typically the female will die just after hatching would naturally occur (even for infertile eggs). We have seen females die both earlier and even a full month later . Typically she will exit the den at the end of her life and may wander about restlessly (in the wild, she would be an easy target for predators but in a tank may live a bit longer). I have noted that the mantle is often bloated and lacks control during this end of life senescence. You can offer small food but it is unlikely she will eat.
Ok so the nitrite have gone down considerably, either at zero, or at the very most .05 ppm. The nitrate is between 5 and 10, ammonia is reading zero. So I guess I'm happy with the water readings, hopefully something starts going right soon for Taco.