This is true for a fact that the Dalai Lama was a Shugden practitioner. He admits it himself in public talks, stating immediately afterwards that he had "made a mistaken". How could someone who has complete control over his rebirths lifetime after lifetime, and who is recognised by so many high Lamas as being an incarnation of Avalokiteshvara, suddenly "make a mistaken" like this?
Dalai Lama is known to also have written praises to Shugden, making references to his enlightened nature.
See this prayer:
MELODY OF THE UNCEASING VAJRA
A Propitiation of Mighty Gyalchen Dorje Shugden,
Protector of Conqueror Manjusri Tsongkhapa’s Teachings
HUM
Glory of the wisdom, compassion and power of infinite Buddhas
Miraculously powerful protector of Manjusri Tsongkhapa’s Teachings
Arisen as a lord of all wrathful worldly hosts
Come from the abodes of Tushita, Kechara, and so forth!
Prostrating with devotion of body, speech, and mind
I confess all mistakes and faults in which
Out of delusion, I have contradicted your holy mind:
Accept with forbearance and show your smiling face!
Arising from the sport of non-dual bliss and void
Are offerings and torma of flesh and blood heaped like a mountain
First portions of milk, yogurt, beer and tea swirling like the ocean
Auspicious signs and substances and various animals
Peaceful and wrathful ornaments, enemy-destroying weapons and armor
Amassed samaya substances, outer, inner, and secret, without exception!
Having fulfilled your heart commitment and purified degeneration
By making these actually arranged and visualized offerings
Increase Lozang the Victorious One’s Teachings
And the life span and activities of the Teachings’ upholders!
Further the happiness of beings in the Gaden [Podrang] dominion!
Especially pacify all harm to us, the yogis and entourages
That arises because of previous karma and immediate conditions
And spontaneously accomplish, just as we wish
All good things, both spiritual and temporal!
Grind to dust without remainder
Enemy hordes that think and act perversely
Towards the teachings and lay and ordained people
With potent, accurate, powerful great vajra fire!
Especially, cause the saffron-clad community of Dungkar Monastery
Brightly beautiful in bonds of pure morality
To soar the path of immortal liberation
On unified wings of Sutra and Tantra!
(link to the website:
http://dorjeshugden.com/wp/?page_id=346)
Note that within the first line of the first stanza, Dorje Shugden is referred to as "Glory of the wisdom, compassion and power of infinite Buddhas" and later, invited to come forth from the pure lands of Buddhas, "Tushita, Kechara and so forth". Why would he write such a praise to a mere spirit, if that is what he claims it to be now? And we are to believe this was just all a big mistake he had made? Across so many lifetimes?