Interesting and useful link Durian! I wonder if the e-mail addresses given as contacts could/would accept a query in English about the Villa?
I came across this book written by a British expat describing his experiences in acquiring land and in setting up a municipal organisation (wonderfully "British" with its committees in this far off land!) in Kuling during the period 1894-99 - there is no mention of any Japanese during that time. The role of the Missionaries is quite noteworthy - it would be interesting to know what has happened to their churches! On Page 24 there is mention of the Russians and the fact that several nationalities were involved in buying lots. On page 32 there is mention of the sale of lots for $200 (with a 25% reduction for Missionaries!!) and no indication of any restrictions by nationality in this essentially "British" concession.http://www.kulingamericanschool.org/KASA_2009/KAS_History/Pages/KAS_Story.html#0
As the history of your link states Kuling was certainly occupied by the Japanese during the "Second Sino-Japanese War" - and was indeed relatively close to their southern front lines. Another reference I found relates to some papers about German holdings/Nationals in Kuling during that period - Germany was of course allied with Japan so its nationals would have remained and not been marched off in inhuman conditions to Labour camps and worse!
Your link's history doesn't particularly indicate that revenge attacks at the end of the war resulted in the destruction of Japanese property. My knowledge of the immediate period after the Japanese surrender is limited. - I suspect that Kuling was militarily a bit of a backwater and escaped further damage. The importance of the location to the ruling Communist elite would also have protected the foreign buildings from the depradations of the Red Guards during the Cultural Revolution.