This answer has very little to do with mythology, but I found this question in the "Unanswered" list and thought I should pitch in. The answer is right there at the link in your question:
My Game is an excerpt from a novel in progress. The novel is yet another interpretation of the Mahabharatha. It deals with the events and personalities depicted in the epic in a rational way, in an attempt at another look at the age-old story. The narrator is Sahadeva…
With a little bit of Google searching and other tricks like guessing URLs, I found the two parts where the excerpts were published in the newspaper The Hindu (as the blog mentions):
Sunday, May 29, 2005, Kesava Menon, Sahadeva's Story: My Game
Sunday, Jun 05, 2005, Kesava Menon, Sahadeva's Story II: Blending in
As both of them say,
My Game is an excerpt from a novel in progress.
and
This is the second excerpt from a novel in progress; the first was published in The Hindu Sunday Magazine of May 29.
Who is the author of the novel in progress? It is a fair assumption that as the articles don't attribute the excerpts to anyone else, the novel is one that was being written at the time (2005) by Kesava Menon himself. There is some supporting evidence at the first one, whose introduction contains:
In a sense, Sahadeva's perspective is that of a political reporter. No such profession is known to have existed those many centuries ago. That being so, the novel is essentially one in which a political reporter of today re-examines the epic in a search for new insights.
Well, "the political reporter of today" is Kesava Menon. Who is he? There is some information at this news article from 2009 ("Kesava Menon is Mathrubhumi Editor")
Mr M Kesava Menon has taken over as Editor of Mathrubhumi, a prominent
Malayalam daily, in Kozhikode in Kerala.
Till recently, he was Associate Editor of "The Hindu" newspaper at
Chennai. Born in 1957, Menon is a law graduate and had served in the
Supreme Court and Kerala High Court before taking up journalism.
Having started his stint with the Patriot, Mr Menon moved on to The
Hindu in 1984 as a special correspondent covering the Khalistan
movement, Kashmir, Left and BJP politics in Madhya Pradesh, Uttar
Pradesh and other areas. From 1990 to 1993 he was posted in Pakistan
as foreign correspondent and covered various epochal events including
the Afghan civil war. From 1993 to 1994 he was based in Chennai as
Associate Editor.
From 1994 to 2002 Menon was stationed in Bahrain covering West Asia,
before returning to Chennai in 2002. He has travelled extensively in
the Gulf.
He is the great grandson of K P Kesava Menon, founder-editor of
Mathrubhumi.
There is another short bio with photograph here, in connection with a 2012 event. It does not mention any books published.
With this, searching for ["kesava menon" sahadeva] threw up results like this blog post from 2005 June 5:
The Sunday Magazine section of The Hindu has a interesting new series of extracts from what is supposed to be "a novel in progress." by Kesava Menon.
The only other mention is in this thesis:
Several modern novelistic
retellings have been attempted by Malayalam writers, which include
Randamoozham by M.T. Vasudevan Nair and Ini Njan Urangatte by P.K.
Balakrishnan. A recent prose retelling by Kesava Menon, Sahadeva's Story,
focuses on Sahadeva, who the author says, has a perception of a political
reporter and is also skilled to do spy work for Yudhishthira.
Again it took some URL-guessing to find out what thesis it is. It's this one:
Leena P. Pai (JNU), A Passage through the Mahābhārata Re-Tellings: Study of some Contemporary novels
If you look inside, it's dated July 12, 2005, a month after the newspaper articles. The reference in the bibliography is to
Menon, Krishna. "Sahadeva's Story". The Hindu: Magazine. 29 May 2005, Weekly ed-2: 4.
It is fair to assume that the novel was not yet complete by then, and the meticulous author of the thesis mentioned it based on the newspaper articles. (Well she got the name of the author wrong, but including a mention from 29 June 2005 in a thesis completed before 12 July 2005 is impressive.)
It is also fair to assume, from the fact that there seem to be no other mentions on the internet, that the novel was never completed or published.