Can a devotee accept service that his guru doesn't directly engage in? For instance, I am very much inspired by Indradyumna's Maharaj's festivals. I think such festivals have a broad reach to masses. I don't like the cultural part of these festivals, but the philosophy and prasadam and kirtan can really get people intrigued.

Some time in the future I would like to organize such festivals and do mass book distributions. However, for that I would need a lot of training from Indradyumna Maharaj even though I am aspiring to serve you.

Answer by HH Bhakti Vikāśa Swami:

We are all supposed to be servants of Śrīla Prabhupāda in the saṅkīrtana movement. So, if you are inspired to help with some particular service which pushes forward the saṅkīrtana movement, that’s not against what I’m doing. And if at all I’m to guide you, I’m to guide you to serve in the association of devotees the bona fide activities of the saṅkīrtana movement. 

So by all means: 
nāca, gāo, bhakta-saṅge kara saṅkīrtana
kṛṣṇa-nāma upadeśi’ tāra’ sarva-jana (CC Ādi 7.92)
[‘My dear child, continue dancing, chanting and performing saṅkīrtana in association with devotees. Furthermore, go out and preach the value of chanting kṛṣṇa-nāma, for by this process You will be able to deliver all fallen souls.’]

Caitanya Mahaprabhu Himself received the order to sing and dance, perform saṅkīrtana in the association of devotees and by instructing the holy name to everyone to deliver the whole world. 

So that order is coming in the paramparā, and wherever and however you get the opportunity to help the devotees in, and join with the devotees in spreading the saṅkīrtana movement, do it. It’s not that if you become my disciple, you have to be locked into a little bubble in a little corner. Let’s all be part of Śrīla Prabhupāda’s big family.