"Hiring in progress" since January, but recruiter has gone ghost. Is this a silent rejection or just corporate delay?

I’m looking for advice on a stalled internship process. I interviewed for a technical internship role at Ericsson Austin in mid-January.

The Timeline:

• Jan 27: Recruiter called, said the team wanted to move forward and hiring was "in progress."
• Feb 19: Followed up. Recruiter said approval was delayed due to someone being on vacations, but I'd hear by "next Monday."
• Present: Total silence since then. Recruiter isn't answering emails/texts/voicemails.

Interviewer Response: I reached out to one of my interviewers (Senior Engineer) on LinkedIn. He replied:

"Hi XXX, It was great speaking with you. At this point, the next steps are managed through the formal hiring process, so I’m not able to get any information regarding the status or comment on outcomes. You’ll be contacted directly if there are updates."

The Situation: I’m a PhD student and this is my top choice as the role aligns with my research perfectly. The "hiring in progress" call felt like a verbal offer, but it's been 2 months.

Questions:

1. Does this specific interviewer reply sound like a "soft rejection," or is he just following strict company protocol?
2. Has anyone dealt with Ericsson’s Austin office specifically? Are they known for these 3-month delays?
3. Is it time to escalate to a Director or HR Lead, or is that too risky?