This was discussed in the WT publications shortly after I left in 2001. It disturbed me then and I asked about it. Not too long after that a Questions From Readers (QFR) came out addressing that. Comparing this to this current info might be educational as to any differences in policy. I do agree that the WTS more frequently selling their properties (for another religion's use especially) might be raising questions in some jws mind. Since this QFR came out 17 years ago and we know how jws hate to research, the WTS is doing it for them.
The fellowship that Paul mentions clearly involves worship and spiritual dealings with idolaters and unbelievers. He warned the Corinthians against “partaking of . . . the table of demons.” (1 Corinthians 10:20, 21) Thus, an act of interfaith is that of sharing in worship or of having spiritual communion with other religious organizations. (Exodus 20:5; 23:13; 34:12) When a building that was used by a religious organization is purchased, this is done simply to acquire the basic structure needed for a Kingdom Hall. Before being used as a Kingdom Hall, it is cleared of any relics of false worship. Being thus adjusted, it is dedicated to Jehovah for the sole purpose of worshiping him. There is no sharing or fellowship between true and false worship.
In working out the details regarding such a purchase, contact with the other party should be kept to a minimum and should be strictly business. Members of the Christian congregation do well to bear in mind Paul’s warning not to become “unevenly yoked with unbelievers.” Although we do not feel superior to those who profess other faiths, we avoid socializing with them or getting drawn into their worship.*
What of a congregation’s renting a building that belongs to a religious organization? Renting usually incurs regular contact, which is to be avoided. Even to rent such a building for just one event, the body of elders should consider the following: Will there be any idols and religious symbols inside or outside the building? How will people in the community view our use of the facility? Will anyone in the congregation be stumbled by our using this building? (Matthew 18:6; 1 Corinthians 8:7-13) The elders evaluate these factors and then decide accordingly. Their own conscience and that of the congregation in general must also be taken into account in determining whether to purchase and convert such a building into a Kingdom Hall.
related explanation why not to join or use YMCA facilities
related explanation regarding jws working on religious buildings, etc.
For easier research purposes regarding specific questions that contain similar hypocritical dance arounds: