The Mantra NO. 19 from "Shree Namratnakhya Stotra" is:
ॐ व्रजेश्वराय नमः
OM vrajeshvarAya namaH
As you can see, "नन्दस्वात्मज" ("nandasvAtmaja") Shloka from "Shree Subodhini" by OM VishnuPad VallabhAcharya MahaPrabhu is being cited in Vivarana.
The gist in English: Krishna is Purushottama/ParaBrahman Swaroop only in Shree Vraja-Dham, not in Mathura or other Dhams, so Shree Krishna = ParaBrahman = Purushottama = VrajEshwara:
And Bhavartha dwells on Rupas of Bhagavan Shree Krishna (Shree GusainJi), for example, "Koti-kandarpa-lavanya-svarupa" of Bhagavan Shree Krishna - a term which you can find very often in Shree Gopala SahasraNams/Tantras and which can be translated into English as "Rupa excelling crores of Love-gods in Beauty":
And, by the way, "Shree Brahmanda-Puranam" is also being cited - a Shloka which tells that Bhagavan Shree Krishna and VitthalEsha are Purna-Avataras, while, for example, Shree Kalki and Buddha are just Amsha-Avataras:
Cited from "SHREE NAMRATNAKHYA STOTRA"
#Shree RaghuNathaLala Rachita#, Sanskrit-Hindi