So she called Tucson on the telephone and was presently in conversation with the clerk at Johnny's hotel.
Hotel clerks are usually quite positive that they know what they are supposed to know about their guests.

This clerk interviewed somebody while Mary V held the line, and later returned to assure her that Mr.
Jewel had been seen leaving the lobby the night before, and had not returned.

A strange young gentleman had occupied Mr.Jewel's room.
No, Mr.Jewel had not been seen since last evening.

The clerk was positive, but since Mary V's voice was young and feminine, he permitted her to hold the line while he called the night clerk to the 'phone.
The result was disheartening.

Mr.Jewel had brought in a young man, and later had left the hotel.