The daycare My 2.5 year old son attends follows the red nose guidelines. One of the guidelines is not waking the children from naps. This had been affecting night sleeps and his mood. Can you please advise. Is it safe to wake toddlers from naps?

Red Nose does not have any specific research or Policy Information about waking sleeping children.
This is not part of the Safe Sleeping recommendations from Red Nose.

Red Nose Safe Sleeping program is aimed at reducing the risk of Sudden Unexpected Death in Infancy (SUDI) which includes SIDS & Fatal sleeping accidents.
The issue of waking sleeping children is not known as a risk to the baby, in relation to SUDI.

Raising Children Network might be helpful -https://raisingchildren.net.au/babies/sleep/understanding-sleep/about-sleep#why-is-sleep-important-nav-title

Your own Child/Maternal Health Nurse may be able to provide further information.

I know there has been much discussion amongst Educators in ECEC about this issue, but not sure if there has been any resolution, or what information/research is available about waking sleeping children or its impact on them.
One of the concerns which is often mentioned - is this the best for the child?

Maybe further discussion with the daycare in relation to when your son is placed for sleep might be helpful.
I always suggest that Child Care Services have this discussion with parents & their State Regulatory Authority.