Exceeding Relay contact voltage
The problem with DC over about 40V is that an arc can form much more easily, compared to AC where the 'zero-crossing' provides 100/120 opportunities per second (assuming 'mains') for the initial arc that can occur at the instant of disconnection to extinguish itself.

DC relays are always more expensive at a given current-capability compared to AC, because they need to separate the contacts further to achieve the same current interrupting capability.

Relay voltage ratings are also about insulation materials types, thicknesses, &amp; distances between the contacts and the coil, so even though your circuit may have some mA-scale limited current capability, there's still potential for arc between contacts &amp; coil, depending on how well or poorly the 24VDC-rated relay is designed &amp; manufactured.  I really would recommend going for a relay rated for what you're doing.