We recently ordered cups from a store for a party and they did not arrive on time . The store graciously offered to lend us new different glasses for the party which THEY toviled and we were going to return them ( as the store told us they have what to do with it ) however my wife liked them and we are now keeping them .
Do they need to be re toviled ?
It depends on why the store toveled it. If they toveled it because they want to provide a service to their customers, that is skeptical if it works, and you should tovel them again without a bracha. However, if they toveled it because they use it for eating (as you wrote they have what to do with it), then it is a Jew that toveled it for his personal use and it wouldn’t need tevilah.
Taz Y:D 120- 0, Minchas Yitzchok 1-44, Tevilas Keilim 3 ftnt. 25, M’bais Halevi Y:D pg. 148, Chayei Halevi Y:D 4-57, Ohalei Yishurun 1 ftnt. 112, that it should be toveled again without a bracha. Minchas Osher Bamidbar 68 says it doesn’t need tevila again. See Ohel Yackov 120 ftnt.116.