OpTerra Energy Group interview questions

In July 2017, I submitted a resume for a position with ENGIE (the job description referenced a wholly-owned subsidiary named OpTerra Energy Group), which required preparing responses to four essay questions. The day that I uploaded my completed resume and questionnaire response, I noticed two other job postings on www.Glassdoor.com for OpTerra Energy Group and for GDF Suez, using the same language verbatim as for the ENGIE-attributed job posting, but three different salary ranges were posted by Glassdoor for each firm. Two weeks later, I was contacted by two different HR personnel for an interview, who told me that they represented OpTerra. I asked if it mattered if I posted on the ENGIE website, since the preparation of the four essay responses were required only for the ENGIE listing with a higher salary range than the job posting for OpTerra. The HR staff member told me that there should not be three separate listings for the same position. The interview lasted 40 minutes, culminating in his asking me my salary requirements. I told him that I would need to know what other benefits were offered in order to be able to answer his question. I was then asked how much I made at my previous job, to which I provided a figure. The HR guy then told me that the hiring manager is based in Overland Park, Kansas, and he did not know when that manager would be available to interview me. Two weeks went by and I emailed the HR guy to check on the following step. He sent me a brief email to indicate that my last salary was more than what ENGIE/OpTerra wanted to pay. No further communication occurred until December 2017, when I received an email from ENGIE/OpTerra to indicate that the position had been filled. The HR staff members seemed disorganized, with a female HR person contacting me after I posted with ENGIE first, followed by communication with a male HR person representing OpTerra. I never received an answer if all three divisions were hiring proposal manager staff. I got the impression that the HR staff was part of an outside agency hiring for ENGIE/OpTerra, due to their email addresses. If that is indeed the case, then ENGIE/OpTerra may wish to opt to work with another resource hiring firm that is more knowledgeable and organized.