THC in the plant is in the form of an acid. Heat breaks this acid down into psychoactive THC. Without heat, this THC will stay inactive.

I would suggest grinding the bud into a powder in a coffee grinder. Place the oil in a warm place, anything over 105F is good enough to begin activating the THC acid. The bottom line is you have to heat the bud or else the THC that is in acid form is not psychoactive.

Just do it and see for yourself. I was just encouraging you to consider heating the oil to make it work better. It will still work without heating. If you eat a brownie and it's not enough after 90 minutes then take another. Adjust your recipe as needed for your needs.