Publication of written texts involving the dhamma

One should not make an effort everywhere, should not be another’s hireling, should not live dependent on another, should not go about as a trader in the Dhamma.
Ud 6.2

I am not sure about Dalai Lama's books, wouldn't hold them on par with Sutta.

Please see "The Bhikkhus' Rules: A Guide for Laypeople" by Ven. Ariyesako.

According to the Vinaya (monastic rules), monks are not allowed to receive, give, keep (for their own sake), or deal with money (including buying, selling, trading, investing, exchanging) etc.

However, lay persons acting as stewards, can handle financial affairs for monks and monasteries.

Hence, the financial transactions associated with publication, sales and handling of the proceeds of sales of books and other information media should be handled by lay stewards. Publication transactions include registration of web domains etc.

If needed, exceptions or modifications to minor monastic rules can be made, based on The Great Standards.

In case this answers the question:

Books & Publications

The Gaden Phodrang Foundation of the Dalai Lama manages and coordinates in close cooperation with the Office of His Holiness the Dalai Lama copyright-related matters for books and other publications authored and co-authored by His Holiness the 14th Dalai Lama.

By assigning rights, title and interest in His writings and other publications, His Holiness the Dalai Lama has graciously donated all royalties from these publications to the Gaden Phodrang Foundation of the Dalai Lama. The royalties are one of the major income sources for the foundation’s fund.

The Foundation also commissions major translations throughout the world, which are in the context of preservation of Tibetan Buddhist culture, science and philosophy.

The Tibetan Vinaya including commentaries is apparently pretty large -- now I don't know it, but I assume it's believed that this kind of setup is compliant with it.

Instead of quoting the Tibetan Vinaya, consider these two paragraphs -- from The Pāṭimokkha Rules Translated & Explained by Ṭhānissaro Bhikkhu -- which explain why money donated to help the upkeep of a monk is donated to a steward (a monastery attendant or lay follower).

The protocols surrounding gifts of money and their proper use are quite complex—much more complex than even this long training rule would indicate—and require a detailed explanation. What follows is an attempt to make them clear. If it seems long and involved, remember that the purpose of the protocols is to free bhikkhus from the even more bothersome worries and complexities that come with participating in buying, selling, and monetary matters in general.

This rule is one of four nissaggiya pācittiya rules covering a bhikkhu’s proper relationship to money. The others are NP 18, 19, & 20. Although they sometimes seem to be splitting hairs, they focus precisely on the two acts involving money that are most burdensome to a sensitive mind: In the act of accepting money, or having it accepted in one’s name, one is accepting all the cares, responsibilities, and dangers that come with its ownership; in the act of arranging a trade, one is accepting responsibility for the fairness of the trade—that it undervalues neither the generosity of the person who donated the money nor the goods or services of the person receiving the money in exchange.

I'm not saying this is that same kind of donation -- e.g. for that purpose -- but it does seem similar in being an arm's-length transaction.

I guess your concern may be not that at all, but the rather the idea of "selling Dhamma"...

Incidentally aren't a lot of the Dalai Lama's books co-authored? His name is on the jacket, but the way it happens is that he talks to an author who does the work of turning it into a book.

Personally it seems to me better that it is popularised or published, sold in book-stores, than that it isn't. It isn't the only way to spread Dhamma, but without books many people in the West would have no access at all.