Here is a letter from Srila Prabhupada shoeing his interest in always preaching co-operatively with his god brothers:

New Vrindaban
23 May, 1969
GAUDIYA MISSION... Ver mais
Att: Secretary
Dear Sir:
Kindly accept my humble obeisances. I beg to enclose herewith a copy of a letter received from my Godbrother, Dr. Syama Sundardas Brahmacari, of your Mission. Taking the concluding portion of his letter inviting me to cooperate with the Gaudiya Mission in the matter of my activities of spreading the objective of Srila Prabhupada Bhaktisiddhanta Sarasvati Goswami Maharaja, I am prepared to cooperate with the Gaudiya Mission in all respects, but I do not know under what condition you wish to cooperate with me. But I am prepared to accept any condition for getting your cooperation in full. So I shall be glad to know from you under what condition our cooperation is possible. But I am prepared in every respect and I shall await your reply with interest.
So far as my starting a separate organization known as International Society for Krishna Consciousness, it was inevitable because none of our godbrothers are cooperating with one another. Every one of us is conducting his own institution, and there is difference of opinion even between Gaudiya Mission and Gaudiya Math.
So if it is now possible to combine ourselves together, I shall be the first man to welcome this good opportunity. But apart from others, if Gaudiya Mission is prepared to cooperate with me, I am prepared to accept this cooperation in any condition. Please therefore let me know your terms of cooperation, and I shall be very glad to consider it. It has been suggested by Dr. Syama Sundardas Brahmacari that we cooperate at least in London, and I shall be glad to know your terms of cooperation.
Thanking you in anticipation for your early reply.
Sincerely yours,
A.C. Bhaktivedanta Swami

Srila Prabhupada says he is prepared to accept any condition for getting your co-operation in full. This is the true Spirit of Srila Prabhupada and the same spirit that has been demonstrated by Srila Gurudeva. Therefor it 100% clear that they are in the same line. Srila Prabhupada says if it is possible to combine ourselves together I shall be the first man to welcome this good opportunity. Srila Prabhupada says he will be first not that we should not go but we should run to willingly co-operate and preach together. This is the proper mood.