Karm Yog is Karm Sanyaas Yog

Ch 18.49
"He whose intellect is unattached everywhere, who has subdued his self, from whom desire has disappeared, he by renunciation attains the supreme state of freedom from action".

A Karm Yogee is engaged in intense activities. He seems to know no rest. But what actually he is at the core of his heart requires to be studied. He does not get attached like water flowing from one side to the other side of a bridge. The bridge is unaffected by the flow of the river. The state of actionlessness and Brahm Avasthaa are one and the same.

18.50.
"Learn from Me in brief, O Kaunteya, how reaching such perfection, he attains to Brahman, that supreme consummation of knowledge."

The very plan and purpose of Nature is to incessantly struggle towards perfection.
The Siddhi that is open to man leads him to immortality, to immutation and to beatitude.
Minds have to undergo modifications influenced by internal promptings and external situations.
A pure mind is fit for Brahm Gyaan and the Yogee who gains in Brahm Gyaan becomes Brahm himself.

18.51.
"Endowed with pure understanding, restraining the self with firmness, turning away fro sound and other objects, and abandoning attraction and aversion."

Anything is pure if it is unaffected by extraneous objects.
A serene and equipoised intellect fixed on pure consciousness is designated as pure understanding.
Thought of the body rarely crosses the mind of a perfect Saadhak.
The body clings to him just as the shadow clings to all objects.
Firmness in the attainment of this perfection leads him to Brahm Avasthaa.

18.52
"Dwelling in solitude, eating but little speech, body and mind subdued, always engaged in meditation and concentration, endued with dispassion"

As a ripe fruit that has severed its connection with the tree, no more goes back to it, the Yogee no more gives any thought to the worldly enjoyments and his dispassion is superb.

18.53
"Having abandoned egoism, violence, arrogance, desire, enmity, property, free from the notion of "mine" and peaceful, he is fit to become Brahm.

When all the disturbing factors are eliminated from the mind, its resting in peacefulness is a matter of course. The Yogee imbued with these excellences is fit for becoming Brahm.

18.54
"Becoming Brahm, serene minded he neither grieves nor desires. The same to all beings, he obtains supreme devotion to Me."

The Lord makes no artificial difference between Gyaan and Bhakti. Though there are some preliminary differences, they become one and the same at their culmination. Gyaan and Bhakti are the obverse and reverse of the same coin of a perfected personality. A Brahm Gyaanee is simultaneously a Bhakt of Eeshwar. He holds all beings with reverence and consider that they are all veritable manifestation if Eeshwar.

18.55
"By devotion he knows Me in truth, what and who I am; Then having known Me in truth, he forthwith enters into Me."

Love makes way to the inaccessible and opens the door to the impossible.
The Bhakt understands the Lord well because he sees with the eye of love.
Bhakti and Gyaan are like two wings of a bird in the consideration of a Saadhak.
He understands that his Lord is both Sa-Gun Brahm and Nir-Gun Brahm. After knowing his own relationship with the Lord, he gives himself over entirely to Him.
The lord accepts him as His own self.
The knower of Brahman becomes Brahman.

18.56
"Doing continually all actions whatsoever, taking refuge in Me, by My grace he reaches the eternal undecaying Abode."

As Gyaan and Bhakti are the same in their supreme state, Gyaan and Karm are also the same in their climax.
The Saadhak established in Sattwa does not renounce Karm. Having renounce his agency to Karm, he has no weariness with intense activity.

As Shree Ramakrishna Paramahans says - "To be ever engaged in Karm is not the real goal of life. It is only a means to godhood.
Work done without attachment leads the Saadhak to Godhood.
We should not mistake the means for the end.
The road to a town is not the town itself.